Cps Question.

[JStoked]

Long story short. I just got a 7mgte revived again. New own head gasket, arp studs. Any way the car started up and I had a vaccum leak. Fixed that and the car started right up again, I let it run for about 30 minutes it ran fine and sounded great. I shut it off because I thought I was done for they day. Being happy that it was running I went to go the and start it again, no cel light know and no start. So here is my question the wires on my plug that goes into my cps is bad( bare wires, and all the normal stuff) I have the end of the harness I need to fix it. But those bad wires at the cps could they cause the no cel light?

 

[SC61 MK3]

No cel check the ecu for power

 

[3p141592654]

Assuming the MIL lamp and wiring is good, then you have no power to the ECU. Start with the EFI, IGN, GAUGE fuses, and work forward.

 

[JStoked]

Well I changed out the plug on the cps. Still nothing. So I got a crazy idea. I turned the key on and checked the voltage at the b+ terminal in the diagnose box. Nothing no power. So I had a crazy idea to use a jumper wire and jump it from the battery to the b+ terminal. Boom CEL lighr (or MIL what ever you call it) came on and the car fired right up.

 

[3p141592654]

Okay, good, some progress.

B+ is actuated by the ECU itself through the main relay. You need to figure out why the main relay is not actuating. The ignition switch (IGSW) input should turn on the MREL output from the ECU, which then controls the main relay.

Check BATT has 12 V all the time.

Check to see if IGSW has 12V with the key on.

If it does, check that MREL has 12 V with key on.

If it does, then the main relay is probably bad.

 

[JStoked]

Ok thank you man. First thing I did was replace the main relay. So I will check the other thing tomorrow. Thank you for your help.

 

[7M4EVR]

Check ur fuses with a test light i had an issue like this turned out to be the "main" fuse iirc

 

[JStoked]

I already did that. But thank you for your info.

 

[7M4EVR]

Did u check fuses or just main relay...there is a efi main relay and an actual fuse that is labeled main. Just want to make sure

 

[jetjock]

A fuse labeled main? Where on the car would that be located?

 

[JStoked]

^ I agree jj. I don't know where that fuse is either.

 

[jetjock]

No such labeled fuse exists. Stick with what 3p is telling you. If you don't have B+ at the diag box with the key on your main relay isn't being energized. And bum CPS wiring will prevent starting but can't stop the MIL from coming on.

 

[7M4EVR]

So I went out and looked at my fuse diagram covering my fuse panel and the word "main" is wrote in from the PO where the IGN fuse is. I apoligize for the bad info, my problem was the IGN fuse....Im dumb

 

[JStoked]

Lol it's all good man. Thank you for trying to help out. And yes jj I'm working on checking all that and thank you very much for your info.