gm codes
#1
gm codes
hi all my service engine soon light comes on for a brief period while driving then goes out when I checked the code it comes up with 12. the vechicle is a 1988 chevy pickup with a 305 5.0 tbi. when I check the gm codes they start at 13
#3
gm codes
I have jumpered a and b on the connector when I turn on the ign. the service engine light flashes once pauses then flashes twice ......I belive this represents 12 the light had not come on before testing ....do I have to wait till the light comes on again then test for codes again thanks again
#4
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Join Date: Apr 2002
Location: Pittsburgh,Pa
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The light will flash code 12 a total of 3 times,which means no rpm reference pulse.This is normal because the engine is not running,it will go to the next code after that.Again it will repeat 3 times and go to the next code and so on.I believe your counting the code properly just wait for more.By the way some codes will not set instantly,there are parameters that need to be met.Good Luck