LS2 6.0L vss output testing
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LS2 6.0L vss output testing just finished doing a LS2 6.0L swap from an 05 Chevy ssr into a 1968 firebird. Everything is working good but I do not have any signal coming from what is supposed to be the speed signal output to the guages. I am running a wiring harness from SSP and coming from the blue connector on the ECU is the grey wire connected to pin #21 how can I check to see if this is Puting out a signal. I am running Dacota digital vhx Guages and according to Dacota digital there should be no compatibility problems with the signal. When I try to program the spedometer it doesn't pick up any pulse signals. I tested ohms from ECU connector pin# 21 to the input to the Dacota digital box and it was 0.00 any help would be greatly appreciated. I talked to the guys at Dacota digital and he tolde me that with a dvom in AC voltage it should be reading at least 3v and I would assume vary up from there depending on the speed of the relucter ring but I'm getting nothing. Does this seem right? I'm wondering if it might be a bad ECU not outing out the signal or if ssp might have turned this function off then the tuned the Ecu (if thats even possible) I know the ECU is getting a good signal because I can get a live data reading from my scan tool on mph jus nothing from pin 21 as far as I can tell.
What trans and VSS are you running?
They are correct on the AC voltage output. If your ecu is reading the speed, the VSS, wiring and ecu are fine.
Is your speedometer looking for a sine wave signal?
They are correct on the AC voltage output. If your ecu is reading the speed, the VSS, wiring and ecu are fine.
Is your speedometer looking for a sine wave signal?
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Its a 4l60E and OEM vss the engine and trans both came out of the same 05 Chevy ssr. I am getting an output signal from the ECU bit it is varying between .099 and .200 depending on speed it goes up and down like it should coming from a reluctor ring creating its own voltage its just not the 3 volts that I was told it needed. I'm starting to think the problem is with Dacota digital Guages. I just wish I could get a straight answer from someone how to test the output from the ECU to be 100% sure before I make them send me another Guage set. The guy at ssp said something about the signal needing to be converted for the Dacota digital Guages but when I called Dacota digital yesterday they tolde that there was no problem with there system reading the OEM speed output signal. Maybe I was just talking to someone who didn't know what they were talking about. I'm loosing my mind and this firebird is going to drive me insane.
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I believe I have found the problem. I am getting a reading but it is to low. I am going off of pin #21 that is the ground side of the vss i am going to try to tie into the unused pin #45 that is the vss high and see if it works. luckaly I had a spare harness to use to steel an ECU pin out of. I will post my results eather this weekend or monday when I test it out im not sure yet if im going to work threw this weekend or not. Here is what I found as far as pinouts go for the VSS on the ECU
Pin #21 in Blue C1 (out to BCM)
Pin #48 in Blue C1 (out to BCM)
and
C3 Pin #45 in Grey C3 (automatic trans vss high)
Pin #21 in Blue C1 (out to BCM)
Pin #48 in Blue C1 (out to BCM)
and
C3 Pin #45 in Grey C3 (automatic trans vss high)
