advise on no start/no CEL

[supraduper]

so im driving home last night and my car starts driving funny, as if it were detonating or was starting to skip... it progressively got worse

to the point where i stepped on the clutch and it died, after it died it would not restart...

thought maybe the engine overheated based on how it drove before if died... but it didnt plenty of coolant and the temp gauge never spiked..

but i am thinking its an electrical issue.. the CEL no longer comes on when the key is turned...

tested the EFI relay under the hood, good
tested the main relay behind drivers kick panel, good
all fuses, good


anyone expirience anything like this?
tips? ideas??

 

[TomFraser]

grounds...

ECU is not getting power, check the ground bolt on the intake manifold

 

[supraduper]

yea, i knew that if the CEL doesnt illuminate with the key on, then the ecu isnt powering..

but yea... i ended up f-ing around with it... and im pretty sure my circuit opening relay was the culprit.... i took it out and when i put it back in it fired right up...

so the opening relay is in my future

 

[Satan]

After messing with tucking away some of the aftermarket alarm wiring, I get a crank no start issue. No spark, fuel, etc.

I am not getting the Main EFI relay to click, no CEL, no power to the ECU. There is power at the EFI fuse and relay... Just doesn't click/start the EFI system going. Replaced the Circuit Open Relay, and Main EFI one with known-good ones.

Checked at the ign. switch and not getting any power from the ignition switch, to the black/orange wire, right at the connection to the switch itself.

I am going to doublecheck the factory alarm arm/disarm connections, but doubt that would be the issue.

Has anyone ever seen the ignition switch go bad? I may have another one, without the lock/cylinder on it, so I may try changing it out as well.

Edit: Tested ignition switch according to TRSM (page BE-15) and continuity is good. Out of ideas now.

 

[Satan]

Wow, I was hoping there'd be alot more info/replies by now.

Looks like the IGSW continuity tested good, but no power is being sent to the ECU (from IG2) to get the main relay going (B/O wire coming from IGSW to ECU. It does have good continuity to the ECU.

I changed out the IG and EFI fuses/relays and just can't figure out why the 12V is not on that wire, from the switch.

I am looking for disconnected grounds to see if I can find one. Others have mentioned the fusebox at the engine bay, but the only thing I can think of there is the "in-wire" fusible link, which is in the white wire going to the battery. However, if it was that, then there would not be any power going to the IGSW or accessories.

Stumped.



SOLVED: Started to play around with the fusebox in the engine bay. Swapped out all of the fuses/relays. It was VERY hard to see, but looks like the AM2 fuse had blown. So hard to see, that I did a continuity test on it to very that it was blown.

Someone had recommended changing out all the fuses anyways... My situation would have been fixed long ago, had I done that 1st. Use a flashlight & magnifying glass on these fuses. You'll be suprised how little is there and a small crack in the connection will stump you too.

 

[Supra87T]

Check these power sources and get back to us.

http://cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=51

 

[shaeff]

Check these power sources and get back to us.

http://cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=51

He figured it out already.

For future reference, if a fuse isn't obviously blown, I use my DVOM to check each one I pull. Been there, done that, spent days looking for a problem that turned out to be one of the first fuses I checked. That was several years ago, and I'll never make that mistake again.

 

[Supra87T]

He figured it out already.

Looks like he edited the post 8 mins after I posted that... lol

 

[shaeff]

Quiet, you! ::moebaker::

:runs away brandishing ban-stick: