VSS - ECM output voltage range?
Thread Starter
Teching In
Joined: Oct 2010
Posts: 7
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From: Ocean Springs, MS
VSS - ECM output voltage range? I've seen a lot of threads on VSS and ECM troubleshooting but I can't find anything as in the weeds as I'm looking for. I'm trouble shooting VSS on (let's call it) a 4th gen Camaro. ECM reads the VSS signal as good (speed works on live data log and in software) and is currently outputting a .06 -> .48 VAC pulse to the gauge cluster (pin 50, green/white on ECM). Any one know if this is a good PPM output range? Long story short the speedo and odometer don't work and I've tested everything up to the speedo. I just don't know if this is "good" output. Before I go buying a new gauge cluster I figured someone on here would know.
I've seen a lot of threads on VSS and ECM troubleshooting but I can't find anything as in the weeds as I'm looking for. I'm trouble shooting VSS on (let's call it) a 4th gen Camaro. ECM reads the VSS signal as good (speed works on live data log and in software) and is currently outputting a .06 -> .48 VAC pulse to the gauge cluster (pin 50, green/white on ECM). Any one know if this is a good PPM output range? Long story short the speedo and odometer don't work and I've tested everything up to the speedo. I just don't know if this is "good" output. Before I go buying a new gauge cluster I figured someone on here would know.
Did it ever work correctly?
How are you reading this signal, unless you're using a scope you're not seeing the signal. It is a variable freq pulse not a varing voltage. Dash clusters fail at a much higher rate then the vss output on a pcm
Thread Starter
Teching In
Joined: Oct 2010
Posts: 7
Likes: 0
From: Ocean Springs, MS
Is the cluster a 4th gen Camaro or is it a 4th gen pcm in some other vehicle?
Did it ever work correctly?
How are you reading this signal, unless you're using a scope you're not seeing the signal. It is a variable freq pulse not a varing voltage. Dash clusters fail at a much higher rate then the vss output on a pcm
Did it ever work correctly?
How are you reading this signal, unless you're using a scope you're not seeing the signal. It is a variable freq pulse not a varing voltage. Dash clusters fail at a much higher rate then the vss output on a pcm
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