PROM chip and diagnostics function
Thread Starter
Burning Brakes
Joined: Dec 2003
Posts: 1,183
Likes: 1
From: MidOhio
PROM chip and diagnostics function
I just had the owner of an '88 I'm interested in tell me he thinks the original PROM chip (Mem-Cal or whatever GM calls it) is required for the diagnostic functions to work. He doesn't have the original chip. It was replaced with an aftermarket chip by a previous owner. Anyone out there knowledgeable on this? Thanks, pre-emptivly.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Even with an aftermarket chip you can still jumper ALDL pins A&B (the two upper right pins), turn on the key and watch the codes flash or start the engine and the ECM will go into Field Test mode so you can see if the ECM is going into closed loop mode.
Take a paper clip with you next time you check out that '88 and see for your self.
Take a paper clip with you next time you check out that '88 and see for your self.
Thread Starter
Burning Brakes
Joined: Dec 2003
Posts: 1,183
Likes: 1
From: MidOhio
The blinking code readout is all I'll probably ever use so that's a relief. I'm not inclined to go to a dealer and pay a bunch to have them hook up their fancy computer-more of a back yard/ under the tree type of mechanic. I'm wondering if the aftermarket PROM chips won't work with an "official" GM service computer like at a dealer due to a propritary ID code or such? What do you think about aftermarket scan tools?
Drifting
Joined: Jul 2002
Posts: 1,273
Likes: 0
From: Olathe, KS USA
Originally Posted by tonymax2
What do you think about aftermarket scan tools?
