Speedo quit working
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Today the speedo quit working on my camaro without any warning at all. So where do I start? The speedo gets it's signal from the VSS, correct? Is there a way to test the VSS, or just replace it and see if that fixes the problem? Is there anything else it could be? All other guages and lights work fine.
Thanks in advance for any input.
Thanks in advance for any input.
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Originally Posted by @nthony
connect a voltmeter to the VSS wire and see if its getting a signal from the PCM. also it may be stripped out because i think they are all made of plastic.
Which wire do I check, what should the reading be?
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yes its on the tailshaft.
i dont know the colors of the wires, or which ones go where offhand.
i dont know the colors of the wires, or which ones go where offhand.
Originally Posted by LT-x7
The VSS is located on the tail shaft, correct?
Which wire do I check, what should the reading be?
Which wire do I check, what should the reading be?
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I still haven't found a place to buy the VSS, but I had another idea I want to run by anyone willing to listen. I currently have no CEL and I've been driving with no speedo all week. If the ecm get's a signal from the VSS wouldn't it throw a code and a CEL if the VSS didn't work right? Is there something on the speedo end that could make it suddenly quit working?
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Either my brain isnt working right now or I havent heard the term "CEL" before. The VSS sends the signal to the PCM, then the PCM sends it to the IPC. BTW, the VSS wires are purple w/white tracer for the high signal and light green w/black tracer for the low signal of the circuit.
If you have anyway to get your hands on a scan tool, you really need to see if the PCM is detecting a speed signal. If the PCM detects a problem in the VSS circuit, it will default the speedo to 0 mph.
Basically you will want to check for continuity between the VSS and the PCM. Disconnect the battery, then disconnect connector # 2 of the PCM. Pin 20 is the VSS low signal and pin 21 is VSS high signal. If the wiring is good between the PCM and the VSS, then check for continutiy between the PCM (connector #2, pin #50, dark green w/white tracer) and pin # B8 at the back of the IPC. If all wiring is good, then you either have a VSS problem or an IPC problem.
As said above, its probably the VSS, but I wouldnt rule out the IPC as a possible cause...I've replaced many of those too.
If you have anyway to get your hands on a scan tool, you really need to see if the PCM is detecting a speed signal. If the PCM detects a problem in the VSS circuit, it will default the speedo to 0 mph.
Basically you will want to check for continuity between the VSS and the PCM. Disconnect the battery, then disconnect connector # 2 of the PCM. Pin 20 is the VSS low signal and pin 21 is VSS high signal. If the wiring is good between the PCM and the VSS, then check for continutiy between the PCM (connector #2, pin #50, dark green w/white tracer) and pin # B8 at the back of the IPC. If all wiring is good, then you either have a VSS problem or an IPC problem.
As said above, its probably the VSS, but I wouldnt rule out the IPC as a possible cause...I've replaced many of those too.
Last edited by joshp14; 09-22-2006 at 09:45 PM.
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CEL= check engine light
Now what does IPC stand for?
Do you happen to know the part # for the VSS and a place to get it? Dealer only?
So I won't have a check engine light with a bad VSS?
Thanks for your help.
Now what does IPC stand for?
Do you happen to know the part # for the VSS and a place to get it? Dealer only?
So I won't have a check engine light with a bad VSS?
Thanks for your help.
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Ah ok, I always use the "SES" term. IPC = Instrument Panel Cluster
I dont know the p/n for the VSS...call the dealer, probably isnt too bad in price...may be available at a local auto store...not sure though never priced one through a auto store. You may not have a SES due to a bad VSS.
I dont know the p/n for the VSS...call the dealer, probably isnt too bad in price...may be available at a local auto store...not sure though never priced one through a auto store. You may not have a SES due to a bad VSS.