asonofabeach69 Posted April 8, 2008 Report Posted April 8, 2008 Well Im just about completely out of ideas, my speedo and odometer do not operate, they havent since I got the car. Well so far i have replaced the instument cluster, that was not the problem, they i replaced the VSS (what a pain) that did not fix the problem. We also checked the connections at the computer and there seems to be no issues there. Well late tonight we observed next to none voltage going to the cluster harness in slot C5 (dark green wire) which seems to be the appropriate one for the speedo. now Im basically stumped, it could be an internal computer problem or a cut in the wire somewhere between the cluster and the ecm right? could it be something else...maybe. the whole thing is driving me nuts. Well anyways if anyone can help me with this situation please do so, any ideas on how i can solve this aggravation would be great. Im tired of process of elimination! it costs me too much money! Quote
89SupremeCutty Posted April 8, 2008 Report Posted April 8, 2008 i would think it might be a broken wire someplace, either between where the vss plugs in and the computer, or between the computer and instrument cluster. i don't think it's the computer itself. that's all i can think of at this hour that might be wrong. Quote
93CutlassSupreme Posted April 8, 2008 Report Posted April 8, 2008 i would think it might be a broken wire someplace, either between where the vss plugs in and the computer, or between the computer and instrument cluster. Yeah, I'd do a continuity test on those two lengths of wire. Quote
Pontiac6KSTEAWD Posted April 8, 2008 Report Posted April 8, 2008 I would probly do a voltage test on the wires, that go to the VSS, and see if the voltage coming out of the VSS changes while driving. if that does change, then find the same wire at the computer, and check for the same thing again. If the voltages, or milivots, change, check also the same thing at the back of the cluster. Sooner or later you will find a place where the voltages dont move while driving. Go back to the last place you checked, and work your way to the point where you didnt get voltage change, and you will find it, and can fix it. You dont have to physically be driving the car. Put the front end up on jack stands, with the parking brake set, or a block in front and back of the wheels. Quote
asonofabeach69 Posted April 8, 2008 Author Report Posted April 8, 2008 This sucks Id imagine following the lengths of these wires is like navigating a labryinth So if I understand this correctly, the 2 wires out of the VSS should be the same 2 wires into the computer? So do I test voltage at the computer side or the VSS side. I dont mean to sound ignorant but man its all frustrating, and just so I understand clearly I know its a dark green wire from the cluster to the computer and Its a yellow and purple wire from the sensor to the computer, right? So I pretty much going to test the wires from the sensor to the computer first because that is the shortest distance and then work from there. thanks for all the help. Quote
Pontiac6KSTEAWD Posted April 8, 2008 Report Posted April 8, 2008 I am not entirely sure on that one. I had to do this on a Cavalier, and the computer is in the cabin, I am not sure if it splits off, or what, with a W-body. Quote
ismellrealbad Posted April 9, 2008 Report Posted April 9, 2008 Your PCM should be located in the engine bay p/s side under a fairly larger black cover in front of the overflow tank, if I'm correct and assuming you haven't already gotten that far Too bad its not OBD2, you could just hoop up a scan too and see if the PCM is getting a signal and skip that step. PS, props to another jersey guy on the board. Quote
Crazy K Posted April 9, 2008 Report Posted April 9, 2008 WHAT YEAR OF CAR AND WHAT MOTOR AND TRANS? If it is a 93... does the car shift gears as it is supposed to when driven, if it has the E tranny? if so, then the pcm is getting the vss signal. to try a test... unplug the vss and see if you see a difference or total lack of shifting fromnthe trans. Quote
asonofabeach69 Posted April 9, 2008 Author Report Posted April 9, 2008 1993 3.4L LQ1 4T60E, Im probably gonna get back at it this weekend and figure out whats goin on Quote
Crazy K Posted April 9, 2008 Report Posted April 9, 2008 1993 3.4L LQ1 4T60E, Im probably gonna get back at it this weekend and figure out whats goin on ok. simple question: does the tranny shift by itself at all in the D or OD gears? Quote
asonofabeach69 Posted April 10, 2008 Author Report Posted April 10, 2008 1993 3.4L LQ1 4T60E, Im probably gonna get back at it this weekend and figure out whats goin on ok. simple question: does the tranny shift by itself at all in the D or OD gears? yea the tranny shifts fine by itself in OD and D Quote
Crazy K Posted April 10, 2008 Report Posted April 10, 2008 then you could have... break in the wiring to the cluster. might be a wiring pin that has backed out. the VSS wire is green. corrupted ecm chip (someone here had one that made the say it was doing 120 when they did like 75... but it also speed governed the car as if it was going that fast at 75. bad pcm? the first is most likely. the pcm has to be getting a speed signal to shift. Quote
rockfangd Posted April 10, 2008 Report Posted April 10, 2008 then you could have... break in the wiring to the cluster. might be a wiring pin that has backed out. the VSS wire is green. corrupted ecm chip (someone here had one that made the say it was doing 120 when they did like 75... but it also speed governed the car as if it was going that fast at 75. bad pcm? the first is most likely. the pcm has to be getting a speed signal to shift. very true ken. how is it supposed to shift without a speed signal Quote
asonofabeach69 Posted April 10, 2008 Author Report Posted April 10, 2008 thanks for all the imput guys, im thinking one of the possible areas for a break in the wire is behind the radio, when i bought the car there was a aftermarket headunit in the car (that i since replaced) whoever put that radio in may have caused a break in the wire. The speedo hasnt worked at all since ive owned the car. Quote
pontiacmaniac94 Posted April 10, 2008 Report Posted April 10, 2008 why dont you replace the speedo from one in the junkyard? just a thought. could it be your instrument panel isnt working right? Quote
asonofabeach69 Posted April 10, 2008 Author Report Posted April 10, 2008 why dont you replace the speedo from one in the junkyard? just a thought. could it be your instrument panel isnt working right? already did that, that was my first move lol Quote
pontiacmaniac94 Posted April 13, 2008 Report Posted April 13, 2008 why dont you replace the speedo from one in the junkyard? just a thought. could it be your instrument panel isnt working right? already did that, that was my first move lol well, sorry man, i got nothing for you. you could pull off the radiator cap and put a new car underneath it Quote
Crazy K Posted April 13, 2008 Report Posted April 13, 2008 got a digital voltmeter? do a continuity check on the green vss wire from the pcm to the cluster. I might be able to get those pinouts.... Quote
asonofabeach69 Posted April 14, 2008 Author Report Posted April 14, 2008 why dont you replace the speedo from one in the junkyard? just a thought. could it be your instrument panel isnt working right? already did that, that was my first move lol well, sorry man, i got nothing for you. you could pull off the radiator cap and put a new car underneath it lol i wish i would have thought of that originally Quote
Q-Ball Posted April 14, 2008 Report Posted April 14, 2008 Just a thought, maybe the wheel speed sensor? Quote
asonofabeach69 Posted April 14, 2008 Author Report Posted April 14, 2008 Just a thought, maybe the wheel speed sensor? isnt that essentially the same thing as a vss? maybe i am wrong Quote
93CutlassSupreme Posted April 14, 2008 Report Posted April 14, 2008 Wheel Speed Sensors are part of the ABS system and shouldn't have anything to do with the speedometer. Quote
89SupremeCutty Posted April 15, 2008 Report Posted April 15, 2008 gotta be a broken wire or short to ground from the ecm to the cluster. that's all i can think of. Quote
Pontiac6KSTEAWD Posted April 15, 2008 Report Posted April 15, 2008 Does his tripometer work? Or Odometer? Quote
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