I have a 2000 blazer a rat ate through the wire harness and fried the computer. I got a wire harness and computer from the local pick and pull and need the steps to program my key into the computer

 

Here you go





George

 

Yeah so a little bit about the car every thing is new. Brand new distributor, new ignition coil and control module, new crankshaft position sensor, new cap rotor wires and plugs, and I got a brand new programed computer from orielly. That's when we found out the wire harness was damaged so we warranty out the computer got another programmed unit. Went to scrap yard and got a used harness and computer just in case. Both the new warranty replacement and used computer succuss on program the security key however I still have no spark out of the coil. Put a high lever scanner on the car and computer is seeing no rpm reference as engine is cranking

 

The passlock system defeats the fuel injectors not the ignition. Usually the truck starts for a few seconds, the fuel injectors are cut off and the truck stalls. If you have no spark that's a different problem.

Spark is CPK>VCM>ICM>coil>distr>wires>plugs. No coil spark can be power, grounds, wires, connectors, VCM, sensor, ICM, coil. You can either start at the coil and work backwards or the CPK forward. Another approach is to check power and grounds to the VCM, coil, ICM and CPK first. No rpm during cranking implies CPK, VCM or their respective powers/grounds/wires/connectors. Let me know if you want me to help you diagnose the point of failure.

George

 

Let's start with the crank sensor. How do I check that?

 

The best way is to watch the output signal during cranking with an oscilloscope. Do you have a scope?

If not then you can look for output pulses with a digital meter while turning the engine by hand and test power and ground at the sensor:

https://troubleshootmyvehicle.com/gm...crank-sensor-1


George