Burned contacts on the key switch cause loss of voltage or low voltage to LOTS of things, including the ignition coil, fuel pump relay, computer, sensors, shift solenoids on the valve body in the pan of the automatic transmission, and can cause LOTS of problems, including fuel pump not running, no spark, trans not shifting into all gears, really hard shifts and more, depending on which of the 6 contacts are burned. Sometimes the SES (Service Engine Soon / Check engine) light comes on and sometimes it does NOT come on. The DTCs usually tell you what the problems are but not necessarily what the root cause is.
I suggest that if you ever have a set of problems that seem to be unrelated but are happening simultaneously, look for electrical problems, starting with the key switch.
Hope this helps. It sure worked for me. No problems at all since I replaced the key switch. BTW, I am not talking about the cylinder lock, I am talking about the electrical part of the switch. It's a plastic black cube about 1-1/4 in on all sides and includes a soldered on wiring harness. Costs about $110 at a NAPA dealer. This is not a Chevy dealer-only part.
A D V E R T I S E M E N T S
Burned contacts on the key switch cause loss of voltage or low voltage to LOTS of things, including the ignition coil, fuel pump relay, computer, sensors, shift solenoids on the valve body in the pan of the automatic transmission, and can cause LOTS of problems, including fuel pump not running, no spark, trans not shifting into all gears, really hard shifts and more, depending on which of the 6 contacts are burned. Sometimes the SES (Service Engine Soon / Check engine) light comes on and sometimes it does NOT come on. The DTCs usually tell you what the problems are but not necessarily what the root cause is.
I suggest that if you ever have a set of problems that seem to be unrelated but are happening simultaneously, look for electrical problems, starting with the key switch.
Hope this helps. It sure worked for me. No problems at all since I replaced the key switch. BTW, I am not talking about the cylinder lock, I am talking about the electrical part of the switch. It's a plastic black cube about 1-1/4 in on all sides and includes a soldered on wiring harness. Costs about $110 at a NAPA dealer. This is not a Chevy dealer-only part.
- Diane G., San Jose, CA, US