Service Wrench and SES Light Behavior after Manual PCM Swap

[KJ_LS1_96]

So I just finished my manual swap on my 1996 SL1 and everything seems to run and drive great. (Well besides my questionable driving skill...)

The only hiccup is that I have both the Service Wrench (which occasionally flashes) and SES lights on. Code from the SES is P1336, crankshaft position sensor variation not learned. I presume that this is because the PCM was swapped to a 1997 manual PCM with the same options. I would prefer not to go to a dealer and do not have a scan tool with crank relearn capability so I just figure I will leave this code and let it resolve itself. That is a thing right, that the P1336 will just make the PCM do its own relearn after so many miles?

Then the Service Wrench I just want to know that this is unlikely to be any mechanical issue. It does not come on when I start the car until about 10 or 20 seconds have passed. I actually suspect that it is just on because I have bulbs out, because I pulled the instrument panel during the swap to check all my bulbs and found that MANY of them were out, and I did not have enough spares to replace them all . So, I just wanna make sure that the Service Wrench light is probably just on because I have a couple bulbs missing. I am just kind of confused by the flashing...

Anyways, thanks for help on either of the light issues. Also thanks for all the help from this forum in general on advice for the manual swap because there is NO WAY I could have done it without this forum. Thanks again!

[fetchitfido]

The Service light with the Wrench icon is only for non-emission issue's, 99% of the time it's for a bulb in the gauge cluster.

Re P1336: Nothing in the ignition timing system does a self-relearn of the crank position. Has to be initiated with a scan tool.
A Local shop did it for me on a '00 Chevy 2500 for the "rip-off" price of $10.00 (yes, a single $10 bill). Years later I got a fake laptop based Tech II and tried it myself on a '01 2500HD but being the dumbass I am I hit buttons too fast and initiated the relearn with the engine off and blew it up while trying to start. At least make sure the engine is running before doing the relearn...

I didn't have to do a relearn on a '93 SL2 when I swapped a '94 SC2 PCM into it. Might have gotten slightly higher MPG but only 2 things told me it was swapped...no hesitation when the auto-PCM thought it should be shifting and the stock PCM's speed limiter was 115mph while the SC2 was on the high side of 125mph.

[bluesl2]

Along with the bulbs in the cluster you have left out, 1997 model years had the low fuel light and 1996 model years did not. The 1997 PCM is probably looking for the low fuel light and not seeing it.

[trottida]

Originally Posted by bluesl2

Along with the bulbs in the cluster you have left out, 1997 model years had the low fuel light and 1996 model years did not. The 1997 PCM is probably looking for the low fuel light and not seeing it.

That can likely be solved with a cluster swap however the mileage is stored in the cluster. A 97-98 analogue or a 98-99 digital cluster would likely work. The 98 model year had both analog and digital. The analog version was the same 97 & 98. There was a mid year change over from analog to digital in the 98 run and they are compatible.