Long story http://www.ls1.com/forums/f6/i-need-...49/index2.html
Short story tired to connect my HPTuners up and it says it can not connect to VCM. This is the first time I have tried to connect to this car.
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Long story http://www.ls1.com/forums/f6/i-need-...49/index2.html
Short story tired to connect my HPTuners up and it says it can not connect to VCM. This is the first time I have tried to connect to this car.
:dunno:
Checked all fuses and replaced battery. Still can not connect
have you checked the fuse for the obd connector? It's on the same circuit as the cig lighter. That would be the first place I would check.
Battery has a good charge?
Harness on the VCM good and tight?
I checked ALL fuses by sight and by volt meter. Then tonight rechecked the improtant fuses. Also the cig light has power.
Ed it is a brand new battery I bought tonight. I didn't check it, but it turns the starter with no problems.
Are you trying to scan or read your VCM? If you can't do either try reading another car just to make sure your cable is ok.
reading 12.4 volts at the battery
I have tired the scanner and the editor. Neither will connect. I have 6 of my 8 credits left. I use to on my orginal car.
I will go try to connect to another car brb.
You won't waste a credit if you are just reading.Quote:
Originally Posted by blackcar
is this through a laptop with a usb port or are you using a usb adapter? I've seen those adapters cause problems. Can you plug the cable in and read your available credits and things like that? What version software are you using?
It hooked up to our 2001 Surburban with no problems.
It is an old lap top but it does have USB plugs. Yes I was able to pull up my old car and read i had used two credits on it.
I'm using the newest version of HPT off the website. Running XP on the laptop. Reformatted the laptop over the weekend and put the newest version of hpt on it.
sounds like it's on the car end then. I would check for power at the plug with a volt meter
pinout for connector
OBD II Connector Pinout
thanks. Printed out and will check tomorow.
Couldn't wait till tomorow. Checking from the ground pin to the power pin. With the key off it checked fine. 12.? volts. With the key in run it dropped to about 4 volts. I know enough about voltage that it is the difference in the voltage that is measured. So I found a ground bolt turned the key on and the power pin had 12 volts the ground pin had 8. Turn the key off and the ground goes back to zero. So how can I tell if it is in the pcm or a ground out wire??
Start simple. Pull the connectors off the pcm and look for corrosion on the pins. That would probably be the first place I would start. I'm not sure on that OBD port harness how it runs back to the pcm but I *think* it's serial.
I will recheck the pins on the PCM, closer this time. I looked at them before but didn't see anything wrong. But there is a bunch and they are small.
Update Still no start
Found the Crank position sensor was broken. I must have broke it while pulling the exhaust manifold out during the header install. Fixed that and it still won't start.
I found out there are two grounds on the ODB II port. A chassis ground and a signal ground. The chassis ground is good. It is the signal ground that is showing 10 volts with the key in run. When I pull the 20 amp eng sensor fuse it goes down to about 2 volts. According to my Haynes book the eng sensor fuse powers the O2 sensors, stop lamp switch, Reverse inhibit solenoid, skip, shift solenoid, and the MAF. I unplugged everything except the stop lamp switch and the short is still there.
How can I tell if the short is in the PCM or the PCM is bad? Anybody got any other ideas? I'm at a loss.
Still haven't found the problem. There have been some updates here http://www.ls1.com/forums/f6/i-need-...49/index5.html
Please help. I'm ready to get this car back running and move on to other projects that have been waiting on this. I got asked again today by my wife when I'm going to get so-and-so done.