DTC = Diagnostic Trouble Code. Your Snap on reader should give you them.
It will say something like PO xxxx purge valve solonoid sigal too low or something like that.
I don't use the Snap On so I have to guess as to what it will say. We have the GM TechII and the Volvo VIDA/Vadis machine.
Just got off the phone to my shop foreman about this. I will get the wiring diagram and find out what is driven by the QDM1 and 4 circuit. He did not know right off hand what all is on those QDM's either.
Hang on to the Snap on tester. We will need that to command things on and off while finding the QDM problem.
The door lock problem should be a seperate issue. If the fuse blew as soon as you installed it, that would be a dead short on the supply side of the door lock/courtesy circuit. The circuit feeds bat+ to the door lock switch's, which in turn the switch's feed reversing DC motor's in each door to operate the door locks.
Without the wiring diagram in front of me, I would check and see if there is a penny or something like that in one of the cig lighter's first. I know it sounds odd, but most of the time when I have to find a short in that circuit that is what I find. Kid's will put anything in anyplace in a vehicle. Not saying your kid did it but maybe previous owner. Sometimes spare change is thrown on the console and falls down into the lighter socket. I will also get the diagram for that circuit.
I had to replace a 900.00 cd deck in a 2004 Volvo xc90 because the owners kid had put almost 23 pennies in the cd drive slot :lmao:
You can do this my friend, I have complete confidence in you. It will take some work but we will get it done. :thmbsp:
And it will be a hell of a lot cheaper than shop labor rate. I would guess the average in your area is 90.00/hour. Plus you get to learn how it works.
Late model vehicles are becoming almost unbelievably complex. An example of that would be: Most premium foriegn cars such as Volvo, MB, BMW, etc, use what is called a CANBUS (Controller Area Network BUS by Volvo) network where each of the modules in the vehicle are networked together using a high speed and low speed circuit.
A CEM ( Central Electronic Module) is the traffic cop for the up to 24 different modules on the CANBUS. GM and the domestics are just now going to it. Picture your server there at AK and the headaches it can give you. Now put all that in a rolling, vibrating, 20 below zero to 160 above environment. Software runs it all.
Fortunatly your Pontiac is very early in this design. Not nearly as complicated, but still quite sophisticated in how it works over the older points and carb units. Remember the feedback carbs? YIKES!!!
However, if you stop and think about it, it is quite amazing that these late model vehicle's, when performing correctly will start and run the same way if it is 20 below or 110 in the shade, put out 100 hp per liter of displacement, and still meet ULEV emmision levels.
Maybe I will do the theory thread in Off Topic, or wherever it would be most appropiate. It will be long though.
Ron
