About to use my Tech 1a for the first time, pointers? ---

[alwayscode390]

OK, here is what I found so far, looks like the code 12 was normal?

* "The 90 procedure is:
1.) Ing "OFF"
2.) Ground "K" terminal. (Hold the door bell button)
3.) Turn Ing "ON".
4.) Wait for fault codes to begin flashing, takes about 5 seconds. When DTC's begin flashing, unground "K" for 3 seconds, +/- 1/2 seconds. ( finger off button for 3 seconds)
5.) Ground "K" for 3 seconds, + /- 1/2 seconds. ( push the bell button )
6.) Unground "K" and wait 10 seconds ( finger off button ). Before turning ING "off", verify that the only code is "12" being flashed ( push the bell button to see "12" ). If not repeat from step "1".
That's the book version for a 90. I tried without the mechanical aid & no joy. Once I red necked the door bell, I got it first shot. If you want to use a toggle switch it may be easier?

Under step 6 it says "make sure code 12 is the only one there" . What exactly is a code 12 telling you?

THEN after messing with my Tech 1 with the door open a long time ( interior lights on and the car off powering the Tech 1 ... the car BARELY started. It looks like that may be what set my SYS light without actually setting a code? Here is what I found while searching:

* "A "SYS" code is 99.99% of the time a warning just before the battery craps out. The only other explanation is after an aftermarket radio install"

I'm not quite sure what the aftermarket radio will do in this situation, but I have one installed also... its been in the car for years though.

It looks like everything is good until I go to clear the INFL RST code next ? ---

[ghlkal]

Originally Posted by alwayscode390

OK, here is what I found so far, looks like the code 12 was normal?

That's strange that the Tech 1 shows a code 12. "Code 12" indicates the system is OK, and starts the sequence if there are codes to follow ...

When I'm using the Tech 1, I put the battery tender junior on just to keep the battery topped up.

[alwayscode390]

Thanks for confirming code 12, and for the tip on the tender.

I only saw the code 12 once, then when I erased it I never saw it again.

I hooked up a couple more times w/ a couple different cartridges trying to get the SYS code to delete... and it didn't show code 12 again for me.

I guess when SYS comes up for a battery it doesn't actually throw a code? ---

[mike100]

The 'SYS' is an error with the CCM (or body control computer). You would need to set the diagnostic to 'body' rather than powertrain.

That said, there is a way to get those codes displayed on the orange center gauge LCD without the use of the tech1.

[alwayscode390]

Yeah Mike, I think the procedure is on the post that starts this page in the thread.

Thanks for letting me know which cartridge to use to clear the SYS code... that's definitely going to be a learning experience for me. ---

[ghlkal]

Originally Posted by alwayscode390

I'm not quite sure what the aftermarket radio will do in this situation, but I have one installed also... its been in the car for years though.

There are two lines from the factory head unit that go back to the CCM which usually aren't present on an aftermarket radio. Lines for the LCD and LED dimming circuits are open without the factory radio and CCM codes 72 and 74 can be set. If that happens, SYS will also flash.

The PO had an aftermarket radio in my Z, but I didn't have SYS flashing. Codes 72 and 74 were set though in history though.

There is a fix for this involving adding two resistors in the circuit. (TSB 93-68-9A) I did do this, mainly because I was wondering if it was the cause of my dim dash lights (it wasn't). I think the procedure is on our site somewhere. I've heard that many other owners haven't done the fix and there is no SYS light with an aftermarket radio.