I am doing the single turbo mod on my harness. I can`t seem to figure out what these are.

light green/silver dots
black/white



brown/black
green/white



light green/white/silver dots
black/white



black/white
brown/blue



These just loop around the harness. they are not connected to the harness at all?????
black/red dots


these where wires had no clips on them??????
black/blue/silver dots black/green/red dots

 

does this help?

 

When I rebuilt my emissions harness last year I used a continuity checker and traced every wire back to the yellow connectors which go into the ECU and/or X-05 (blue) and X-14 (white). Both X-05 and X-14 are located on the cabin side of the harness near the ECU. By seeing where these wires go to on the yellow connectors and using the FSM you can identify what they served. Running no emissions, no EGR, no airpump, and no IAC I think I ended up with 17 connectors left on the harness. My 17 were:

IAT
O2
TPS
Water Temp Sender
Knock
(2) Crank Angle
OMP
Coolant Level Switch
Coolant Level to Engine Harness
Cooling Fan Switch
Coolant Temp at Water Pump
Fuel Temp
(4) Injectors

I am not counting the grounds (2 I think).

I later added the IAC for a total of 18. Which leads me to the next bit of advice. Put in three or four spare wires in case you need them for more gauges, etc.

Not trying to answer your question by telling you to go do more work (i.e. trace wires) but I found it a very helpful way to understand the harness and what was going to the ECU to actually run the engine. Before I finished I retested every wire back to the ECU just to make sure.

I have some pdfs I made of the ECU connectors which show what is what. I'll look for them.

Jeff

 

Yuck..... how many miles are on that harness? Based on the pics, I'd recommend springing for a new one.

 

yeah i am starting to shift that way. after thoroughly going through the harness and modifying it almost every thing i touched broke off. I think i have to start looking for a low mile/new harness and just get it converted by one of you pros. I definitely don't have the patients for this type of sh*t


grimple1...I was doing my harness according to your thread but like the impatient jerk that i am i pulled the harness with out labeling the plugs.I spent all night trying to trace wires and still couldn't figure it out. ether way it was a learning experience

 

As of early Jan. Malloy Mazda was selling a new engine harness (N3A1-18-05ZG) for $800. That's the one that runs through the firewall, under all the solenoids and down to the CAS.

The one that runs from the battery, alternator and down to the starter (FD01-67-070K) was $500.

The small one to the coils(N3A3-18-05Z) must be around $80.

 

holy crap that's a rip-off. I know Ray's selling it at a good price but that's just ridiculous that Mazda would charge that much for that harness.

 

Plus for a single turbo or non-sequentials with no emissions you need to completely unwrap your new harness and remove 1/3 to 1/2 of the connectors and associated wires. Then wrap it back up.

Depending on how bad yours is you might want to consider having someone rebuild it or find a single turbo harness for sale.