aftermarket speedo hookup trouble.help!
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aftermarket speedo hookup trouble.help!
*1990 c4 speedo wire needed for gloshift gaugesI know there is a vss.I have located it and I know the purple wire comes off of it is a ground and I need ground side wire for gauge hookup.it is the last one left to do for my gauge cluster.I did all the rest of them but this one is tough.also how do I test vss to determine if it is functioning please. Thanknu.Tuned, over and out*1990 c4 speedo wire needed for gloshift gaugesI know there is a vss.I have located it and I know the purple wire comes off of it is a ground and I need ground side wire for gauge hookup.it is the last one left to do for my gauge cluster.I did all the rest of them but this one is tough.also how do I test vss to determine if it is functioning please. Thanknu.Tuned, over and out
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'90 C4 the VSS is noted as being PPL: LO and YLW: HI. Neither is ID'd as ground and the VSS in a '90 is essentially an AC generator. In the FSM it is noted as such also. No where have I ever seen PPL mentioned as ground. Where have you seen that mentioned?
Do you have a link to the install instructions for your gauge package? If yes post it!
Do you have a link to the install instructions for your gauge package? If yes post it!
Last edited by WVZR-1; Dec 5, 2014 at 02:58 PM.
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I hooked up a test light and back pinned terminals without puncturing wires. Purple and yellow come directly off of the vss. Splicing into the wire there is tough
Not enough slack to get my big hands in there.please help
Not enough slack to get my big hands in there.please help
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I've tried the purple wire on green connector.no success.I've noticed the vss where the connector plugs in and its moist.can trans fluid leak out of there? If it is trans fluid would it create a high resistance connection?
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Spin the VSS and you should get an AC voltage when you check YLW/PPL - voltage should vary. Use a low voltage on your meter BUT AC not DC.
Your VSS in a '90 should have the connector in the center with YLW and PPL wires. VSS could be either white or black but connector in the center.
Your VSS in a '90 should have the connector in the center with YLW and PPL wires. VSS could be either white or black but connector in the center.
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I believe you can use the DKGRN/WHT from R8 (red connector) at the ECM to accomplish what you need. That signal goes to the cruise module and so on. If it were easier to access it at the cruise module then that's what you might want to do. The cruise module though is in the car under the glove box so I doubt easier. It would be on top of the radio receiver box so if you've removed that or are familiar with it then it might be effortless. The DKGRN/WHT would also be accessible from the CCM which is also inside of the car at front of console, the connectors I believe are not accessible easily. Regardless of where you access it you need the DKGRN/WHT from the ECM. Do you have the FSM? If not would you like to buy one? I believe I have both books in very good condition.
Last edited by WVZR-1; Dec 6, 2014 at 08:29 AM.
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The wires behind the factory cluster where were I found everything except the speedo.I am very familiar withit as I have hooked up all wires for the rest of the gauges except the speedo.the speedo has been kicking my butt.
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You need to get the speedo signal from any of the places that I mentioned. There's no place else. It should be very simple now and straight forward DKGRN/WHT from ECM or at the cruise module looks like the easiest. I mentioned it all. I found the wiring scheme earlier today and posted what I assumed would fix it for you. You should be all set. Done!