Fellow techs please confirm diagnosis

wolfman · 09-17-2002, 04:57 AM

Still waiting for a reply on those "other boards" I am working on a recently aquired 91' SL1 Manual. Thanks to the help of a donor car and some new brake parts the car is almost road ready. It starts, idles and drives just fine. At this point everything works perfectly, all gauges, warning lights and the cooling fan cycles normally. Except the SES light. The bulb and wiring check out fine. If I jumper the 2 diagnositic terminals however the SES light does NOT flash and the HOT light and cooling fan come on. The SES light also does not light up on start up. I do not recall seeing this before during my days at Saturn, nor can I think of any other possibility. At this point I am thinking BAD PCM. So do you think I am right? (Oh yeah, and Joey do you have a 100% functional PCM with the epromm intact for my "classic" 91' SL1 manual?)

Joeybagodonuts · 09-17-2002, 02:51 PM

hey wolfie,from waht you describe it simply sound slike a burned out ses bulb, it hasnt lit at ANY point? did you swap it out foranother bulb? it IS common on the early cars for them to be disconected somehwere as ealry saturns threw errant codes (meaning for no reason really) quite often, so i read you visually inspected it but check first to make sure theres actually juice going through the plug and the bulb itself.
yes i do have fully functional pcms (only kind i sell lol) drop me a line at the site for pricing.

wolfman · 09-18-2002, 01:01 AM

Just an update. The SES light bulb is FINE. Tested with a continuity tester AND swapping it for the oil pressure light where it worked just fine. The SES light NEVER comes on...even at startup. A test of the SES light wire at the PCM connector shows NO outbound signal voltage with key on engine off. Jumpering the diagnostic terminals makes the "HOT" light come on AND the radiator cooling fan until the jumper is removed. WOW I guess I've got everybody stumped!!

**Ssicarman** · 09-18-2002, 02:36 AM

Does the SES light come on on the key on self test with the rest of the dash lights? I have never seen this before myself so you may just be down to making sure that all the wiring is intact, no opens, grounds or shorts. Make sure that the terminals are not backed out anywhere. I say this because last week I had a car in for the major service and could not reprogram it because as I found out the wire from/to the PCM and data link connector was backed out at the PCM connector. Back in place and the TECH II was now talking to the PCM.

Have you tried cracking the PCM open to check for burnt circuits? I think though that like you I would just leave it for now and see if you can happen on a cheap PCM. Maybe see what Joey can do for you. You could very well be right on the quad driver.

OX · 09-18-2002, 03:05 AM

if my recollection serves me correctly here...if the SES light is not coming on...and a code 12 is not present when testing the SES circuit, it could be a faulty PCM.

Anyone have anything else to add here? Am I somewhat close? LOL