View Full Version : OBD II Code Readers

July 28th, 2006, 07:08 AM
Can someone give me a simple explanation of how these work ? My Chevy trucks message center can be a pain in the uh! um! wallet. Check Engine Soon has lit up on several occasions(usually after fueling up). $85.00 to have the GM garage reset it ...The last time it happened I borrowed a reader from a friend and plugged it in <Fuel Mode> error and <Engine Misfire>error Do you wish to delete (Iknow what delete means) YES .Now I've got one of these little gadgets in my tool box and it cost me $49.00. But there is a PC program and cable that can be had for more money.I wonder what the language is.and it only works with Windows.

July 28th, 2006, 08:05 AM
When something like this happens on my Pontiac Grand Am GT right after fueling, (the check engine and another light comes on) it means the gas cap isn't on tight enough... (In NJ they only have full serve gas stations..)



July 28th, 2006, 11:37 AM
If all you are looking to do is clear the cars DTC (diagnostic trouble codes) then typically, in the vast majority of OBDII compliant cars, all you need to do is disconnect the positive terminal of the battery for a few minutes. I had to do this after my wife drove for a week with the gas cap off of her Neon.

If you keep having a code trip after actually clearing the PCM then you have a mechanical problem that needs to be repaired or you need to make sure your gas cap is fully tightened.

July 28th, 2006, 12:58 PM
OK, every GM(olds cutlass 89, 93 silverado, and 97 silverado) we've owned has had engine lights on, we just ignore it and nothing ever happens..lol
GM has crumby sensors, they go bad a lot..lol
Luckily, my 83 silverado is too old for sensor problems, and I removed the o2 sensor on my explorer, and replaced it with a sensor emulator..lol...so no more engine lights on it.

Terry Yager
July 28th, 2006, 01:08 PM
The light comes on after every 20,000 miles, to remind you to test the O-sensor, which has a ~20,000 life expectancy. Disconnecting the battery for 20 minutes should clear all the codes, but it also erases all other info stored in the computer, setting everything back to factory defaults, so the engine might run a little 'funny' for a few minutes.