OBD not communicating
#1
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I hope that this is the right section for this question, if it isnt i apologize.
Anyways, I went to get my car inspected after buying it and ended up getting a big fat R. It wasnt my bald tires, loud exhaust or lowered suspension either. It wasnt even my nonfunctional horn. Apparently the OBD would not communicate with the inspection computer. The car is a 98, but its had a lot of work particularly in the engine dept. and i know its also been tuned. On a couple of the OBD system tests it read "Not Ready" on the inspection sheet and I was told that is what I failed for.
I also seem to have developed a battery problem right around the same time. The general concensus is that the two problems are related; that because of the weak battery the PCM couldnt function properly so it wouldnt store the necassary data. Or something like that.. electronics dont mix very well with me.
Regardless, Im hoping that that is all it was and that with the new battery I just installed it should clear itself up no problem. But, I want to cover my bases and get as many oppinions as possible. Are there other things I should be looking out for? What are some other possible culprits?
Anyways, I went to get my car inspected after buying it and ended up getting a big fat R. It wasnt my bald tires, loud exhaust or lowered suspension either. It wasnt even my nonfunctional horn. Apparently the OBD would not communicate with the inspection computer. The car is a 98, but its had a lot of work particularly in the engine dept. and i know its also been tuned. On a couple of the OBD system tests it read "Not Ready" on the inspection sheet and I was told that is what I failed for.
I also seem to have developed a battery problem right around the same time. The general concensus is that the two problems are related; that because of the weak battery the PCM couldnt function properly so it wouldnt store the necassary data. Or something like that.. electronics dont mix very well with me.
Regardless, Im hoping that that is all it was and that with the new battery I just installed it should clear itself up no problem. But, I want to cover my bases and get as many oppinions as possible. Are there other things I should be looking out for? What are some other possible culprits?
#3
TECH Senior Member
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Yeah check the CIG/ACCY fuse. Thinking it's OK though since they found the not readys? Since you had the battery disconnected it probably reset all the readiness tests and will need some miles/drivecycles to pass. Try www.obdii.com/drivecycle.html
#5
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i just looked at the OBD drivecycle you gave me the link for. It calls for accelerating to 55 and then down to 20 without shifting or anything. So at 20mph the highest gear i can be in is probably 3rd. Is it ok to shift during that 55mph run from fifth to third for the deceleration section?