OBD 1 Transaxle Code Help

[clemsonsaturn]

Since my 1992 SL2 is up and running I have an SES light. I went ahead and read the codes:

Engine:
Code 23 (IAT)
Code 26 (most likely EGR fault)

Those shouldn't be any problem fixing, already found lots of info about them here.

Transaxle: (here's where I'm stumped)
I'm assuming that on 1991 and 1992 models equiped with an automatic transmission that the codes are displayed with the "SHIFT TO D2" light. Am I correct in this assumption?

The SHIFT TO D2 light flashes 6 times, pause, 1 flash (I'm assuming this means it's ready to give you a code?). The light will then flash 6 times, pause, 2 flashes. Then after those codes are given, it will go back to the SES light and repeat the engine codes.

My problem is there is no code 61 or 62 according to my Haynes manual. There are codes 16 and 26 though (no first gear and TCC stuck on respectively). I'm not sure if I'm reading the codes right though because the 6 flashes happens first, then the pause, then the 1 flash or 2 flash depending. I'm 99% sure it's not 2 flashes, pause, 6 flashes because of the length of the pause.

Does anyone have any input? What are probable causes of codes 16 and 26? Is it as simple as a sensor not being plugged back in (the car was driving fine with no codes prior to this)?

Any information would be greatly appreciated .

[Luke]

> Fm Clemson <
> Code 26 (most likely EGR fault) <

No, it would be related to the IAT. If you had an EGR issue, the probability would be very high that a code 32 would have been set. Lacking that code, I'd eliminate the EGR as an issue.

I'm a little confused with your comments regarding your "SHIFT TO D2". If memory serves me correctly, those blinks should also appear in three cycles. It should be the same as the 3 cycles that the codes 23 and 26 appeared through the SES light.

(( Unfortunately, I'm working from another computer and another location; This one does not have all of my "Saturn" sources ))

[clemsonsaturn]

Originally Posted by Luke

I'm a little confused with your comments regarding your "SHIFT TO D2". If memory serves me correctly, those blinks should also appear in three cycles. It should be the same as the 3 cycles that the codes 23 and 26 appeared through the SES light.

(( Unfortunately, I'm working from another computer and another location; This one does not have all of my "Saturn" sources ))

you're right Luke, the "Shift to D2" light DOES appear in cycles of 3, just like the SES light.

The codes are:

6 flashes, pause, 1 flash (3 cycles)
6 flashes, pause, 2 flashes (3 cycles)

I've checked it 4 times already and after the SES cycles, it immediately goes to the 6 flashes. So, that's makes me want to eliminate code 16 and 26 since it's doing the 6 cycles FIRST.

Any ideas? I'm really stumped on this one .

[geartooth94]

you are on the right track with having the engine codes use the SES light and the transaxle codes use the "Shift to D2" light.

From the FSM:

"...If only information flags are stored and a diagnostic check is completed, DTC 12 will flash followed by any engine diag. trouble codes, no DTC 11 will be flashed, but the "Shift to D2" lamp will begin to flash transaxle flags."

"DTC 26 may also be logged if the Shift to D2 lamp circuit has a fault."

Also, transaxle information flags:
61: PCM Programmable Read-Only Memory Failure
62: PCM Interrupt Failure

Sadly the repair for both these flags is to reset the PCM, go for a drive and if they come back then to replace the PCM.

[wolfman]

As posted by geartooth above, the transaxle learned memory for the transaxle is not being "remembered" by the PCM. Check first to make SURE (as in with a TEST LIGHT or pull each one out and LOOK) all the fuses in BOTH fuse boxes are good. Then make SURE that the PCM main harness plug is plugged in and tight. The other thing to look for is corrosion on the main wiring harness to UHJB (underhood fuse box) plug UNDER the fuse box for corrsion on the connectors. If all that checks out...time to find a good used or new PCM.

[clemsonsaturn]

Thanks a lot geartooth and wolfman! That clears things up for me a lot. I will check all the fuses and for any corrosion. If there are no problems there, I will look for a used PCM. That should be no problem though. I'm fairly sure I can pick one up very cheap.