Just got my rebuild running today.. Was setting timing and notied I'm not getting power to my trailing coils. I verified it with a meter. Where does the power come from? Thanks.

 

If you have power to the leading, but not the trailing, then it must be a wiring problem, because they are both fed from the same contacts of the main relay...Check your connectors...Also, one of the power wires goes directly to one of the coils, while another goes to the ignitor section, then heads back to the other coil. Basically the same circuit, nonetheless...

 

I checked for power at the 2 prong connector that feeds 12V to the trailing coil. no power there. just can't figure where it comes from. Maybe the ecu?

 

Maybe a stupid question but, did you switch the ignition to "ON" position?
It's sometimes difficult to get a good reading from the timing light due to it's weak spark.
Check the connectors for corrosion or it's ground. The brackets serves as ground.

 

Yah ignition was on.. will take another look at it tommorow.. I think I need aother ecu. I have no warning lights and all gauges in cluster including tach. My dash lights work though. I bought this 90 vert at an auction with no eng and rebuilt a core i bought. So do you think the ecu is messed up?

 

Ohhhh..I thought it was a simple engine rebuild. The tach gets signal off of the trailing coil.
There's a factory service manual at: www.iluvmyrx7.com
Look through the values and resistance in there to check anything is blown in the ECU. Was there any part of the engine harness that was burnt indicating engine fire?? There many stock parts available at: www.thepartstrader.com

The CPU (located next to the interior fuse box) may be bad if your horn, instruments etc doesn't work.
Boy, you got your hands full. LOL

 

The ECU has nothing to do with any of your problems.

The Trail coils 12v feed wire is black/yellow. It is the same wire that feeds the Lead Coils. IF you have lead coil power then it follows you should have trail coil power. Unless the wire is physically broken prior to getting to the trail coil.

No gauges working and no idiot lights most likely means a blown fuse. Try the METER fuse. It feeds both.

 

where is the meter fuse? My horn and all dash lights/dimmer switch all work. It's just the gauges. Does the same wire feed both coils. I would think so. This afternoon I will look and see for a broken wire.

 

&&&&&&where is the meter fuse? &&&&&&&&

In the fuse box.

 

I asked because I checked all the fuses. Thought it might be somewhere else. No wonder you have 8,000 + posts

 

I'm not sure what else it could be. If all the meters doesn't work it's most likely a blown fuse but if that's ok then.....????????
It's odd that ALL the meters don't work.
Maybe someone reading this had a similar problem other than a fuse.

 

Only other thing they would have in common is the connector for the gauge cluster...

 

The clock in the warning light cluster works but all the lights don't. I swapped the cluster and same thing..

 

Did you check the alternator connector? If it's not connected, the idiot lights doesn't light up. Well not all .
I think your CPU is bad.
If that is bad, you won't get any lights since that controls the alt warning light relay, buzzer, horn , hazards and something else.
If your horn, hazard lights , turn signal doesn't work. The CPU is bad.

 

Attached are the two schematics that relate to the problems. I've posted both more than twenty times in the past.

There is a free FSM online.

In the FAQ, one of the very first threads on this site.......there is a jpg of both fuse boxes..........with the word, METER over the designated spot for the METER fuse.

Digital volt meters can be had for less than twenty five bucks at Radio Shack.

Putting a ground on the white/black wire at the small plug on the altermator should result in all the idiot lights lighting up if the key is to ON.

The clock is fed from a different fuse than the idiot lights. See attachment.

My worst answer is better than your best question.

 

Hailers: King of Schematic Attachments

 

My horn, hazard lights and turn signals all work. I took my meter and ohm checked a few things. First i took of the water temp wire from the sensor near the oil filter and did a ohm test with that wire and the coresponding wire in the cluster wiring. the wire was good. I also did the same for the trailing coil - wire to the wire in the cluster and that wire was good. All I can think of from looking at the wiring diagram is the ignition wire that i think powers all the gauges. Tell me if I'm wrong from the diagrams. Or it might be a ground. I will check the power wire and ground wires on the cluster wiring and let you guys know what i find. Thanks for all the help so far.

 

I finally figured it out... I got a wiring diagram to figure out what each wire in the cluster does. First I checked the gound wires and they were good. I checked pin L or #12 on the white connector and got no power when ignition was turned on. Then i ran a power wire to that plug and installed cluster. All the gauges and warning light cluster worked as advertised.. I wonder how hard it is to find out where that ignition wire goes? It's a black/yellow wire. Now I can feel better taking it for a spin.. This car has been a real pain.. Bought it with no engine then bought a core engine to rebuild. This was my first rebuild and everything is working out in the end. From the diagram Hailers posted the wire goes straight to the igition switch through the 7.5 fuse. Thanks for all the help....

 

Hmmm....really odd.
I was suspecting a corrosion on the cluster panel. Well, rather than tracing the ignition wire, you could tap into a 12V switched wire. You really don't want to start tracing the wires all over under the dash.

 

Or...you could get the meter and start looking where the break is. Did you check the meter fuse connector if there is continuity?

 

*****Hailers posted the wire goes straight to the igition switch through the 7.5 fuse. Thanks for all the help....******

Nope. The black/yellow wire goes from connector H-01 at the back of the idiot light cluster.......to connector X-10......then to the 7.5 amp fuse and from the fuse to the ignition harness just about a foot below and fwd of the ignition switch (X-02).

X-10 is a twenty one pin connector b/t the Front (F) and the Instrumant panel harnesses. It's located inside the car. To the left and up. Not far from the FUSE BOX. That's what the manual shows. I don't remember the exact location.

 

Attached is a jpg of the connector location.

Question. Does your tach work when the engine is ON?

As for X-10, follow the harness from the two round connectors at the instrument panel downwards and fwd. They should intersect the X-10.

I just realized I fucked up on my post about two above this post. I was thinking about the idiot lights NOT the Combination Meter.

 

About my fuckup on the Combination Meter. The wire goes from the back of the meter (C01 connector) to another plug about a foot away called C03. C03 is a twenty one pin plug.

I'm talking series four only. Not series five. Series five is similar......I think.

 

The 7.5 fuse is good. It runs more than just the cluster. I wilol try and trace from the cluster to the fuse. That is where the break should be i think. If not will trace further. If I can't find break I can just run a switch power there.. Thanks again for the help..

 

Maybe you guys could help me out. I don't mean to hijack the thread, but it is on the subject of coils...so here goes:

My TII cranks very strongly. It has compression. The leads connected to the trailing coil spark, the leads connected to the leading coils do not. I used a test light and tested the 2 prong connector that supplies the power to the leading coil and it lights up fine....why would it not be sparking? One of my friends thinks that the coil is bad...is it common for coils in the s4's or s5's to go bad?