Ok I have a 1996 Tahoe 4x4, 5.7 Vortec Engine and the service engine soon light is on and when I went to check the codes with my reader it powers on, but says no link. I had talked to my friend and he told me to try it on another vehicle and see if it will read it and if so to check all the fuses in my tahoe. So I hooked it up to my 97 Silverado and 96 Ranger and it worked perfectly. So I checked every fuse under the hood and in the dash in my Tahoe, and every one was good and I even followed the wires from the plug until it disappeared into the wiring harness and it all looked good. However, when I hook my reader back up to it, it powers on but continues to say "no link" everytime. Does anyone know what would make it do this??
Register today for free or log-in if already registered to remove this ad!
Well I checked my tahoe and it doesn't have a ECM (Engine Control Module) under the dash, it has a PCM (Powertrain Control Module) under the hood, right beside the fuse box and it says the only way to switch it is to take it to a dealership and have them switch it and reprogram it, but i'm not sure thats what's wrong and don't want to waste the money, because the only thing that isn't working right is it reads no link when I plug my code reader up.
I have checked the wires under the dash and the wires that come out of the firewall and everything looks untouched. Does anyone know any other way to read the codes other than using a code reader, because I know on a vehicle that requires an obd1 reader, you can jump a wire across the ports in the plug for the reader and get the codes that way??
does your scan tool a internal battery to power it up?
If your sure the dlc has power and grd. With a voltmeter check voltage on the serial data line...pin #2 of the dlc. It should be less than 7volts. If higher there is a short to voltage on the serial data line.