pcrea

went to smog 92 ls400 and smog tech said that cel diag light should show with ignition set to on
the other icons show but no cel....therefore smog check = automatic fail
anyone seen this problem.....I disconnected (-) battery 10 min no help
removed ECU-B & ECU-IG fuses 10 min no help...

RA40

iTrader: (6)

Welcome to Club Lexus.

This will get you started.
https://www.clublexus.com/forums/ls4...capacitor.html

LScowboyLS

if disconnecting the negative battery cable doesn't help, then neither will pulling any fuse (when you disconnect the neg. battery cable, you have pretty much pulled them all )

you can try pulling negative battery cable for 24 hours, but this is likely either an ECU caps issue or a bad ground.

dc893

how long have you had the car? I have seen people just remove the bulb when the cel comes on so they can sell it easier. The bulb could also just be out. I would pull the cluster out and change the bulb before doing anything with the ECU.

python

iTrader: (4)

omg..the bulb is burned out....ECU CAPS?! I would check the bulb first..geezus pete

LScowboyLS

have NEVER seen one of these burn out


now this is actually a real possibility


yeah, you know, like one of the MOST common issues on 92-97 LS400

PureDrifter

iTrader: (10)

LSCowboyLS and Python both of you exit this thread. Not up for debate, PM me if you need to discuss.

OP- troubleshoot by elimating things you can verify to be good. Supply +12v to the lead for the CEL, if it lights up that eliminates the bulb and cluster as an issue. (pinout for the ECU should reveal the right wires to use, verify before doing), then look at the ECU itself.

pcrea

Have had since 2000 or so. But didn't notice missing cel til smog date.....so between last smog & now something caused to go out.....several years ago I did have the cut or broken wire in the trunk wire harness/cable problem that caused dash lights to flicker when open/close trunk...found and crimped offending wire
Could this be affecting the cel icon ? I don't think so

pcrea

Ok. Sounds like a plan...need to locate pin out to measure the 12v to the cel light....it should be same on the other dash lights. Right ?

PureDrifter

iTrader: (10)

yep. Just to confirm, the CEL isn't lighting up at all when you turn the ignition to "on" before starting it?
No response when you jump the terminals to try to get an error code? (http://www.lexls.com/tutorials/intro/codereading.html)

on2u

My CEL also does not show, when this occured the car did not run anymore.

Changed the 8 capacitors with low ESR ones and the car still does not run nor show the CEL.

Trying something else, will let you know if I get anywhere with it.