Can't read code
Thread Starter
3rd Gear
Joined: May 2016
Posts: 3
Likes: 0
Can't read code
My 89 suddenly showed a "service engine soon" display. It does not show at engine start up, but only after warming up for about ten minutes. I jumped the ALDL connector at pins "A & B", only to read a
continual code 12 which never ends. In other words, nothing but code
12 appears. I am trying to smog car in California and won't have a chance of passing showing the flashing display. Car seems to be running fine.
Thanks for any suggestions
continual code 12 which never ends. In other words, nothing but code
12 appears. I am trying to smog car in California and won't have a chance of passing showing the flashing display. Car seems to be running fine.
Thanks for any suggestions
Team Owner
Joined: Sep 2003
Posts: 25,377
Likes: 2,735
My 89 suddenly showed a "service engine soon" display. It does not show at engine start up, but only after warming up for about ten minutes. I jumped the ALDL connector at pins "A & B", only to read a
continual code 12 which never ends. In other words, nothing but code
12 appears. I am trying to smog car in California and won't have a chance of passing showing the flashing display. Car seems to be running fine.
Thanks for any suggestions
continual code 12 which never ends. In other words, nothing but code
12 appears. I am trying to smog car in California and won't have a chance of passing showing the flashing display. Car seems to be running fine.
Thanks for any suggestions
Thread Starter
3rd Gear
Joined: May 2016
Posts: 3
Likes: 0
Thread Starter
3rd Gear
Joined: May 2016
Posts: 3
Likes: 0
Sorry, I misunderstood. With ignition in "key on" position (engine not running), light is solid. It only flashes after 10 mins of driving and continues to flash until shut down. Jumping the ALDL at this point produces only code 12 and nothing else.
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
Most parts stores can't read obd1 codes. If ALDL is jumped while engine is running check engine light will flash indicating O2 sensor flipping from rich to lean. I would check wire from ALDL to ECM for chaffing or or shorting to ground. If there no problem found I would replace ECM
