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Come and join me, let's go far, far down the rabbit hole!
Recently, my engine had to come out for a rebuild. The engine is still out and parts gathering, cleaning, purchasing, etc. is ongoing to get the car back on the road. What has bothered me for some time, even before the engine had to come out, is the state of the emission harness. I performed several repairs, and in the limited running of the car after that, all was fine. However, those were temporary fixes to a few connections. The whole harness is 30 years old and in a state of disrepair. Moving it twice has resulted in several broken connectors. A large section has absolutely no flex whatsoever and very well could end up with crack wires without my knowing. I feel I can no longer trust this harness. Now, if I could simply buy a new harness from Mazda, I would. However, an S5 Turbo Emissions Harness for a USDM car is no longer available. Several places sell very nice replacement harnesses for FDs. For the work involved, and the quality these appear to be, their price is fair. There are also wonderful terminated harnesses available for those switching to an aftermarket ECU. However, I have not found anything that suits my market - new and stock. I am not removing emissions devices. I am not looking for huge power. I am not removing emissions devices. The goal is for it to work, to the best of my ability, as it did when it was driven off the lot in 1991.
So that leaves me with what I see as three options. First, I could continue to repair my current harness. Second, I could find a suitable used harness with less miles and less crisp factor. Or third, and the reason this thread is being written, I can make my own.
Before I really begin, this thread started by pzr2 is a fantastic leaping off point on replacement connectors in the FC. In that thread and several others, many vendors are listed who are fantastic resources of many of the connectors found in our cars. They include, but are certainly not limited to: Corsa Technic, Ballenger Motorsports, Eastern Beaver, and Cycle Terminal. They are not the only places to find these parts, but they are among the most popular. I also rely on Mouser wherever possible, as some money can be saved using them. But it can be very hard to find items there unless you already have some good ways to narrow down your search.
Everything I type here will be relevant to S5 Turbos. There will be much carry over to S5 N/As. I have never owned an S4, so I am not entirely sure what will be relevant there. I know many of the connectors were changed between S4 and S5. I will give as much detailed info on each part as I possibly can, including parts numbers where available, proper terminals when not purchased as a kit, Mazda's nomenclature for which connector that is (from the wiring diagram, specifically my 1991 wiring diagram), and the current sources I know of that stock the part. Also, I'm going to spread this out over several days. I'm still waiting on some things.
Let's begin with the four connectors located inside the vehicle.
Connector B2-23, 16 position male, yellow, Terminals 2A-2P of ECU
-
I found this connector at Mouser, made by TE Connectivity, TE part #174514-7. Ballenger also stocks this connector, but it is pictured in gray. I measured all wires on this connector at 20 AWG (two are shielded wire though, the knock sensor and O2 sensor), so the correct terminal is TE part # 173716, also available from Mouser. I ordered 173716-6, a cut tape at 100 terminals. Note that on several of these part numbers, what comes after the dash changes some aspect of what you are ordering, such as the color of a connector, or the form factor of terminal (loose piece, reel, cut strip).
Connector B2-10, 26 position male, yellow, Terminals 3A-3Z of ECU
I also found this at Mouser, TE Connectivity #174516-7. The 16 inboard terminals are the same as in B2-23. The outer ten terminals, six on one side, four on the other are TE #173631-6 for 20-16 AWG (some of these are heavier gauge ground wires), and of course from Mouser.
Still two more connectors to go inside the passenger compartment, before we break through to beyond the firewall.
Connector X-10, 11 position male, stock orange, replacement in natural, interconnect to Front Harness
Also from TE Connectivity, this is #172497-1. Purchased from Mouser. All wires are either 20 or 16 AWG, the correct terminal is TE #172775-1.
Connector X-11, 20 position male, stock yellow, replacement natural, second interconnect to Front Harness
This is the first of many I could not find on Mouser (at least without hours of searching). It comes from Corsa Technic and was purchased as a convenient kit. It is a Sumitomo 090II unsealed series connector.
That concludes it for tonight, but I will continue on tomorrow.
because the car is RHD vs LHD there are a couple of differences, however it does work.
the engine has the same stuff on it, except only one solenoid on the ACV instead of two, so the harness sits on the engine the same. the ECU pinout is the same.
the difference is that the JDM harness doesn't have the wiper wires (its on a different harness), but its easy enough to depin yours and reuse
difference 2, is that the pinout of the plug under the dash s different, the USA has three, manual, turbo and a/t, the Japanese only used 1, and its like the a/t, same wire colors though, same plug, needs repinning
difference 3 is that the engine to ecu part comes out by the oil filter and goes the other way on the JDM car, however it is long enough to go along the firewall and reach the US ecu spot just fine (its actually slightly longer). this leaves the branch that goes to the afm just the afm and Map wires.
because the car is RHD vs LHD there are a couple of differences, however it does work.
the engine has the same stuff on it, except only one solenoid on the ACV instead of two, so the harness sits on the engine the same. the ECU pinout is the same.
the difference is that the JDM harness doesn't have the wiper wires (its on a different harness), but its easy enough to depin yours and reuse
difference 2, is that the pinout of the plug under the dash s different, the USA has three, manual, turbo and a/t, the Japanese only used 1, and its like the a/t, same wire colors though, same plug, needs repinning
difference 3 is that the engine to ecu part comes out by the oil filter and goes the other way on the JDM car, however it is long enough to go along the firewall and reach the US ecu spot just fine (its actually slightly longer). this leaves the branch that goes to the afm just the afm and Map wires.
So, I did not list it, but I had considered that option. I definitely didn't get as in-depth as you have here with all the differences. However, the differences and the fact I was able to find *almost* everything I need fairly easily swayed me towards making my own. The material cost (I will not include my time researching and the labor to assemble) will be comparable to the cost of a new, incorrect, but mostly correct JDM harness. There are some things I will be doing that will take the cost above, but those are personal choice and would not be necessary if merely trying to replicate exactly as OEM. I will be using Raychem DR-25 heat shrink, expandable sleeve for further abrasion resistance, and labeling all connections.
The first connectors that branch off once the harness goes into the engine bay are very much non-emissions related. They are the wiper motor and cruise control actuator.
Connector D-01, 6 position male, black, Wiper Motor
This was purchased from Corsa Technic as a kit. It is a Sumitomo 250 Armlock connector. This type of connector will reappear several times in various configurations. There are some differences between it and what came on the stock harness. The locking tab has a slightly different shape and terminal retention is by tangs on the bottom side of the terminal. The stock connector has tangless terminals. Eastern Beaver carries the tangless variety, but not in black.
Connector Q-04, 4 position male, white/natural, Cruise Control Actuator
Also purchased from Corsa Technic as a kit. This has the same locking tab profile of the wiper connector, which makes it different than the stock one. The stock connector also has a chassis clip that was clipped to...nothing. This same 250 armlock is available from Corsa Technic with a picture that better matches the locking tab profile of the stock one here. I later found this on Mouser as TE part #172134-1.
For today's update, let's move on to a branch of the harness that has turned into a bit of a problem child.
Connector B2-34, 4 position male, white/natural, Boost Sensor
Refer to one post up and repeat everything about the cruise control actuator connector. Same 4 position Sumitomo 250 armlock. Stock does not have a chassis clip like the cruise control connector did.
Connector G-21, one position male, stock green, Check Connector
Pictured obviously is the stock connector. There is nothing special about its type, it is a Sumitomo 250 armlock. Except it's green and non-stocked everywhere I have looked. TE Connectivity #172128-4, and you can at least see the specs here at Mouser. The datasheet confirms -4 is green for this series. So there are two options. If yours is in good condition, clean it up, put a new terminal in it (stock is tangless!) and call it a day. If yours is unusable, it's a one position armlock available from a variety of places. Mouser has it in black and white. I also just discovered Mouser stocks it in gray, which is an interesting alternative. TE #170032 is the correct tangless terminal. A green label dot could be used to denote the connector's correct color.
Anyway, here's a one position black armlock from Corsa Technic.
Connector B2-35, 5 position female, black, Air Flow Meter
This one has me absolutely stumped. I can't find it anywhere. It's some sort of Sumitomo HM, HW, or MT, but I've come up empty everywhere. I bought one that I took a hunch on, but it wasn't it. But here's the good news. If your connector is in good shape, it can be redone with new terminals and seals. The Sumitomo 090 HM, HW, or MT terminals and seals work perfectly.
Connector B3-04, two position male, yellow, Check Connector
Again, there is nothing special about this connector type. It's a Sumitomo 250 armlock in two position male. But it's yellow. That's TE #172130-7, non-stocked of course. Mouser stocks in natural and black. Here's a two position armlock from Corsa Technic:
More to come later as we keep moving along the harness. We have done ten connectors total so far out of 33 I counted on my harness, but there are several repeats later (injectors and solenoid rack).
Usdm s5 na harness will work on t2. Just have to extend some connectors (tps and cas iirc). I think 2 wires have to be swapped at the ecu connector for the boost control solenoid.
might want to look into that. I used a low mileage s5 na engine harness on my s5 t2 which has 95% of emissions, I’m pretty sure I can run 100% of emissions, solenoids, etc.
Usdm s5 na harness will work on t2. Just have to extend some connectors (tps and cas iirc). I think 2 wires have to be swapped at the ecu connector for the boost control solenoid.
might want to look into that. I used a low mileage s5 na engine harness on my s5 t2 which has 95% of emissions, I’m pretty sure I can run 100% of emissions, solenoids, etc.
Would also need a knock sensor. Again, not insurmountable hurdles, but not the path I am going down.
Our next branch takes us in two different directions. Towards the OMP and also out towards the ACV, BAC, and O2 sensor.
Connector B2-22, 6 position male, white, Oil Metering Pump
and
Connector B2-33, 3 position male, white, Oil Metering Pump
I purchased these as a male/female set from Cycle Terminal. Sumitomo MT090 series and I purchased each as a set because Cycle Terminal offers the matching female side of each of these with the proper chassis clip for the OMP sub-harness. The amount of terminals and seals Cycle Terminal sent me in those bags should tell you we will be revisiting the Sumitomo MT090 series again.
BONUS - 6 position female, gray, Oil Metering Pump
The OMP has its own separate sub-harness. This is the connector that goes into the OMP itself. It is also a sealed Sumitomo MT090 series. Uses the same seals and terminals.
The next branch takes us in the opposite direction of the OMP branch.
Connector B2-19, 2 position female, black, stock white, Bypass Air Control Valve
This appears to be a Sumitomo of some type, but with a different keyway than others. There is an injector connector that works, but this is the exact match. Purchased as a kit from Ballenger Motorsports. They have it pictured in green, but I have purchased twice, and received black each time.
Connector B2-18, two position female, black, Air Control Valve Split Air solenoid
The first of two connections at the ACV. This one is a female for the split air solenoid. It is your typical Sumitomo 250 armlock two position connector. Purchased from Corsa Technic as a kit.
Connector B2-24, two position male, black, Air Control Valve Port Air solenoid
You know the drill. Two position Sumitomo 250 armlock. Purchased from Corsa Technic.
Connector B2-41, one position female, black, Oxygen Sensor
Tyco/AMP Econoseal one position connector. Purchased from Corsa Technic as a kit.
I have made my first mistake. I mixed up the Sumitomo MT and HM series. It appears the OMP should be HM connectors. The information in post #10 should currently be ignored. The MT and HM are very close, but unless swapping both ends, it won't work. And then you would have to continue swapping a connector if you ever needed a new OMP.
I see where I went wrong on the OMP. The 3 position is an MT, as evidenced by these photos showing my brand new female MT fitting my stock harness perfectly.
It's the six position that is not an MT:
Maybe at one time these connectors were in the same series, but it does not appear they are now. I believe the 3 position to have been correctly identified earlier as an MT, but then I got lazy, saw what looked to be the same series and went straight to the MT series for the six position. Now that I look at the pictures more closely, the six position sure does appear to be an HM.
I'll place another Corsa Technic order and confirm this next week. I didn't want to pretty assertively document what now turns out to be a wrong connector, but now I've passed the time limit on editing yesterday's post. C'est la vie!
Okay, one more and I'm done for the night, because this is driving me mildly nuts. The six position female on the OMP sub-harness is an HM or a second six position connector in the MT series that mates to the HMs. I'm not quite sure how I missed that the first time around.
Hey Jerry, just a thought - if you're doing a total rebuild of the harness from the ground up, and don't care about making it cosmetically identical to the OEM harness (but obviously do care about functionality and electrical/mechanical performance), you can substitute the appropriate Deutsch DTM connectors on both ends, as long as the OEM connector on the sensor/output device can be clipped off and replaced with the DTM connector. This would work fine on the OMP, TPS and a number of other sensors on the FC. The Deutsch connectors are environmentally sealed, easy to assemble & work with, and are perfect for the under hood environment. I used a bunch on my FC rewire job (AEM Infinity ECU), and my FD (Link G4+ ECU); I have a build thread in the FD section that talks to that rewire job here - https://www.rx7club.com/build-thread...oject-1149941/
The rewiring content starts on post #12, some info there and links might be useful to you.
Hey Jerry, just a thought - if you're doing a total rebuild of the harness from the ground up, and don't care about making it cosmetically identical to the OEM harness (but obviously do care about functionality and electrical/mechanical performance), you can substitute the appropriate Deutsch DTM connectors on both ends, as long as the OEM connector on the sensor/output device can be clipped off and replaced with the DTM connector. This would work fine on the OMP, TPS and a number of other sensors on the FC. The Deutsch connectors are environmentally sealed, easy to assemble & work with, and are perfect for the under hood environment. I used a bunch on my FC rewire job (AEM Infinity ECU), and my FD (Link G4+ ECU); I have a build thread in the FD section that talks to that rewire job here - https://www.rx7club.com/build-thread...oject-1149941/
The rewiring content starts on post #12, some info there and links might be useful to you.
Another excellent suggestion. Duetsch connectors are widely available and easy to work with. And I'm certainly not afraid of rewiring anything, given what I'm already proposing. But the goal here is to keep it as 100% close to OEM as possible. If I ever needed a new TPS or OMP or anything else, I could quickly swap those parts without the then added step of wiring in a new connector. I hadn't read through your FD thread, but I love it, particularly the A/C parts. While the engine is out, that's another thing I want to tackle on my FC, as it's all out there and never going to be easier to reach.
So after my OMP fiasco, I've realized I currently have incorrect TPS and CAS connectors, for the same reasons mentioned about the OMP connectors. I mixed series and initially purchased the incorrect ones. That situation should soon be rectified, as I'm about to place another order with Corsa Technic, but am awaiting their opinion on something else.
Anyway, let's continue on with what I do have.
Connectors B2-11, B2-12, B2-13, and B2-14, two position female, stock blackish-gray, replacement gray, Fuel Injectors
Widely available from several vendors, but these were purchased from Corsa Technic. Any search of "Denso type fuel injector connector" should bring these up. These may be the connector most people are familiar with, as it is a popular one to be replaced. These Sumitomos are perfect matches in mating and fitment, but cosmetically different than the stock piece.
Connector G-22, one position female, black, Auxiliary Front Fan
This connector is to the temp switch for the auxiliary fan on turbos and automatic transmission cars that is located in front of the A/C condenser. This one is a little tricky to track down. However, Wiring Specialties has this one, available as a pigtail or parts. I of course chose parts.
Connector B2-32, two position female, stock black, replacement red or gray, Water Thermosensor
This is an odd one. It's very similar to a Bosch Jetronic fuel injector connector, except for the oddly placed offset tab. The leg work on this one is all pzr2 on this post. The connector pictured in the first two pictures is indeed from Wiring Specialties. I went one step further and purchased the Aptiv part # he found of 12129143 (12129141 is non-stocked at Mouser). This is the gray connector pictured alongside the other in the third picture. I find this one much more aesthetically pleasing than the red connector. It fits, but I have not found the correct terminals yet. I believe Metri-Pack 280 terminals may work, but I have not ordered any yet to try this.
Metri-pack 280 are huge connectors..I mistakenly thought a mystery connector was a metri-pack 280.it was it was at least twice the scale of the connector..maybe it's a metric-pack 150 I think those are much smaller. going off of pictures you can't easily determine the scale of the connector.
Metri-pack 280 are huge connectors..I mistakenly thought a mystery connector was a metri-pack 280.it was it was at least twice the scale of the connector..maybe it's a metric-pack 150 I think those are much smaller. going off of pictures you can't easily determine the scale of the connector.
The description on Mouser has MP 280 in it. We shall see if it is or not.
Connectors B2-20, B2-25, B2-26, and B2-28, 2 position female, stock orange, green, gray, and blue, replacements black, Solenoid Valve Pressure Regulator Control, Solenoid Valve Pressure Regulator Control No. 2, Solenoid Valve Switch, and Solenoid Valve Relief
This is a Furukawa VC-2S purchased from Corsa Technic. The application list on their site is literally RX-7 solenoid rack. The colors of these are obsolete. Colored heat shrink could be creatively applied on the wires leading up to the connector to identify the original color.
Connector B2-21, 2 position female, blue, Duty Solenoid Valve Boost Pressure Control
Sumitomo MT090 with a different keyway and colored blue. The MT seals and terminals are the appropriate ones. Purchased from Cycle Terminal, it's the second one down.
Connector B2-27, 3 position male, stock green, Check Connector
As with the other check connectors, I'm going to reuse mine to keep the color, and again, this is a 3 position Sumitomo 250 armlock. However, there is one vendor who actually stocks this. The part is a TE #172132-4 stocked by a third party vendor (Waldom Electronics) and listed at Digi-Key and on the Waldom website. I have not attempted to purchase.
Last on this branch is the CAS connector, but still waiting on the correct part after the HM-MT mix-up that led to incorrect connectors for the CAS, OMP, and TPS to be purchased. Corsa Technic says they will be in stock at the end of this week. A shipment from Taiwan is needing to clear customs.
We have almost reached the end of the connectors. The end of the harness splits out two ways, the first is the other two injectors (already covered) and then the throttle body and AWS solenoid.
Connector B2-16, 2 position male, natural/white, Air Supply Valve
Our trusty friend, the Sumitomo 250 armlock. You know where to find it by now.
Connector B2-17, two position male, black, Accelerated Warmup System Solenoid
The last of the Sumitomo 250 armlocks.
In the middle of the last two branches is one lone connector.
Connector C-04, 1 position female, stock white/natural (maybe? Mine is covered in grime), replacement black, Water Temp Sensor (for gauge in instrument cluster)
TE Connectivity #172320-2 from Mouser. They stock this in white and black. It uses terminal TE #170452.
Connector B2-31, 2 position female, stock yellowish, replacement orange, Intake Air Thermosensor
TE Connectivity Part # 172210-4. They call this yellow, I call that orange. Either way it's the IAT connector from Mouser. This uses terminal TE #170324.
Connector B2-42, 1 position male, Knock Sensor
This one has also eluded me. But in a side conversation with j9fd3s, he mentioned the FD knock sensor is a 1 position Tyco/Amp Econoseal, similar to the O2 sensor. I need a new knock sensor anyway, as the filler where the wire comes out was melting onto my trailing plug and plug boot. FD knock sensors cost more than FC knock sensors though (insert joke about cheap FC owners), so I probably will buy a new FC knock sensor and swap out to an Econoseal plug.
And other than the OMP 6 position, the TPS, and the CAS, we have reached the end of the connectors. I'll finalize that and perhaps produce a chart that would make a quicker reference material than this thread of pictures. Then I'll move forward.
Connector B2-30, six position male, stock white, replacement black, Throttle Position Sensor
and
Connector B2-22, six position male, stock white, replacement black, Oil Metering Pump
This is the correct Sumitomo HM sealed six position connector for the OMP and also the TPS that I referenced in post #13. This is available from Corsa Technic in either natural or black. I'm going for stealth and not showing the extra dirt and grime and going with black. Available here.
Connector B2-15, four position female, stock white, replacement black, Crank Angle Sensor
The correct Sumitomo HM sealed connector. I have also chosen black for this one. Available here.
And that's it. Every connector I could find for the S5 emission harness. Other than the knock and AFM, I have found them all, albeit some not in the correct color. Claudio from Tuning Technology said he thinks he can get the S5 AFM connector. I will certainly post here if I get my hands on some. He and I had a good conversation via email as I bought an FC grommet from him.
So, other than connectors, you need some other supplies. The harness has one M8 and two M6 ring terminals for grounding points.
And then, we need wire:
This is all the non-shielded wire I need, plus some others I picked up for other projects (RX-7 related, but not the emission harness). Every color needed was available from https://4rcustomswire.com/ except for B/LG. They also had no length minimum, which is very helpful when ordering large amounts of striped wire.
Oh, almost forgot the grommet I mentioned in the last post.
Purchased from Tuning Technology. Be sure to read his disclaimer. I don't believe this will be an issue for me, but if it is, hey, he warned me.
plan B is that Mazda sells these, for the ND Mx5, part number N243-67-G11
the newer Mazda's have connectors and pigtails available, but pretty sure the connectors are all different
If you haven't purchased your wire yet, I'd highly recommend upgrading from the GXL/TXL spec wire sold by that vendor in your previous post to a M22759/32 spec wire in the appropriate gauge for the circuit application (-# at end of spec, i.e., 18 gauge = M22759/32-18). In addition to having superior Tefzel insulation, the insulation layer on the mil-spec wire is significantly thinner and tougher than what you'll find in a GXL or TXL wire, and the metallurgy is made to be more robust in an automotive under hood environment (i.e., better corrosion resistance, and won't break due to heat cycles or vibration as easily). Compared to GXL/TXL, you'll find it's easier to work with when building your harness, especially if you decide to go all in and try your hand at fabricating a concentric twist harness. If you do, you'll be rewarded with an end product that will be more flexible yet mechanically sturdier, thus it will be much easier to route it where you want under the hood, and less likely to fail due to heat cycles & vibration over time. The only downside I see to working with the mil-spec wire is you'll need a really good & sharp wire stripper to do the job, as that Tefzel insulation is very tough
Pricing wise, you'll end up paying a bit more for the mil-spec stuff than you would for GXL/TXL from that other vendor, but probably not a heck of a lot more. I think ProwireUSA has a 10 foot minimum buy length, but realistically that's probably what you'll need in most cases anyway. To save some $, for the common wiring applications (e.g., +12VDC, power grounds, sensor signal grounds, +5VDC sensor power, etc.) you can use the same color (e.g., all +5VDC = violet, all +5V sensor signal grounds = brown, etc.) and buy larger spools of those colors.
For the twisted/shielded pair CAS wiring, I'd recommend going with a M27500/20SBT23 (20AWG x2 twisted/shielded pair, mil-spec Tefzel insulated). ProwireUSA sells that stuff too.
I'm going to try the TXL for now, but will be using Tefzel mil spec shielded for the wires that require this (knock, O2, and CAS). The goal is still to keep it as OEM as possible. Tefzel throughout may be version 2.0.
09-13-21, 07:53 PM
