QuestionQUESTION: My 2003 town and country minivan failed emissions because they couldn't hook their computer to mine. The dealer said the PMC needs to be replaced - their quote $750.00! They said the price of the part is $587.00 and the rest is labor. On a question asked to you in 2007 you said they were easy to replace. I found a remanufactured PMC for $259. Are remans okay to use? It says it has a lifetime limited warranty. And can I put it in myself to save the big labor cost? I already had to pay them $100 just to diagnose it!
ANSWER: Hi Teri,
The problem is that there is some progamming that needs to be done to mate up the replacement computer to the body computer, etc. parts of the digital data network. And that typically requires the application of the Diagnostic Readout Box at the dealership to do it. For example, if there is a theft system on board, when you hook up the replacement computer it may not be possible to start the engine without the programming having been done.
Have you tried to get fault codes yourself? Turn the ignition key:" on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the odometer window to see if the mileage reading changes to show any 4-digit codes which will verify whether that diagnosis is correct or not. Let me know what they are. If that doesn't work, try for a free readout at an Autozone parts store.
Let me know any numbers.
Roland
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QUESTION: It said P 1684.
I'll take it in to the dealer if they need to do it but do you think a remanufactured part is okay to use?
ANSWER: Hi Teri,
I have no reason to believe a remanufactured would not work.
Interestingly, that 1684 code simply means that the battery was disconnected recently, in the past 50-100 key cycles, and would not disqualify you from emissions once it disappears (in 50-100 key cycles), which it will do after you drive it for sufficient trips. The fact that it was there may be the reason they wouldn't 'pass' you.
Keep checking the codes and when you get no codes then try to pass emissions again. The fact that it is giving you a code readout suggests that it isn't non-functional. As to not being able to hook up to your computer, there are about 6 wires between the reader plug-in socket and the computer which can easily be verified to be connected, or if not connected then can be repaired, without replacing the computer.
You can go to an Autozone parts store and for free they will try to do a readout. If they can successfully get codes now, then the emission people should be able to do so as well.
So you may avoid the cost of replacement entirely.
Roland
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QUESTION: Roland, thanks so much for your help! I hope you don't mind another question. We did replace the battery recently but the check engine light had been on before that time. The dealer told us one of the circuit boards in the computer was "fried" and that we needed to replace it. Could they be misreading it? Will the autozone readout tell me that? I'd love to avoid the cost of replacement if I can.
AnswerHi Teri,
I don't know who did the emission test where it failed due to non-communication. But it certainly appears to be functioning well enough to tell you a fault code by a self-diagnostic readout procedure. Ideally, the socket which is used to do an external readout is working, and that would be revealed if Autozone can get a readout that way. It they can, then the emission people can too. If there was something so bad as to have a 'fried' board I would question how come it seems to do a self-readout. Also. there are codes for malfuntion of the computer, and none of those codes (0600,0601,1685-1698) came forward just now. So I question what the dealer told you. They could be misreading/obfuscating about this situation.
So see what Autozone finds when they to the readout and we'll go from there. Verify that they used a code reader, not the ignition key to get their result.
If, for example you replaced the battery, and then went for the emission test, you may have "failed" because the 1684 code was present. The emission people don't like to see a 1684 as that could be a clue that the owner tried to 'cover up' a real fault by disconnecting the battery. And in fact you can get rid of codes, for a while perhaps, by doing just that. So you could take the paperwork for the battery replacement with you to the emission test and show them the reason for the code 1684 is not disqualifying. They should have some procedure to deal with such a history.
Roland
