Turning ignition switch to start position ! Nothing happens , no click , nothing ?
Circuit Description
Moving the ignition switch to the CRANK position sends a 12 V signal to the PCM Ignition Crank Sense. The PCM verifies that the transmission is in the PARK or NEUTRAL position. The PCM then grounds the control circuit of the START relay. When the START relay is energized it allows voltage to the starter solenoid S terminal.
Starter Solenoid Does Not Click
2
Turn the ignition to the START position.
Does the engine crank?
YES - Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
NO - Go to Step 3
3
Install a scan tool.
Turn ON the ignition, with the engine OFF.
With a scan tool, observe the Crank Request Signal parameter in the PCM data list.
Turn the ignition to the START position.
Does the scan tool display Yes?
YES - Go to Step 5
NO - Go to Step 4
4
Turn ON the ignition, with the engine OFF.
With a scan tool, observe the Crank Request Signal parameter in the PCM data list.
Turn the ignition to the START position.
Does the scan tool display Yes?
YES - Go to Step 11
NO - Go to Range Selector Displays Incorrect Range in Automatic Transaxle - 4T80- E
5
Turn OFF the ignition.
Disconnect the Starter relay.
Turn ON the ignition, with the engine OFF.
Connect a test lamp between the battery positive voltage of the Starter relay coil circuit and a good ground.
Does the test lamp illuminate?
YES - Go to Step 6
NO - Go to Step 19
This is troubleshooting info from GM factory service testing and repair manual .A scan tool isn't necessary , you could use a test light if you knew which pins at the PCM . For example , testing Crank Request Signal parameter in the PCM data list. Find this wire circuit at the PCM , with a test light .When turning the key to start position ,does the test light light ? A factory scan tool just cuts down the time of diagnoses . A wiring diagram is a must for diagnosing this . Free wiring diagrams can be found at
http://www.bbbind.com/free_tsb.html There are videos on youtube on basic automotive electrical trouble shooting , Control module diagnostics . That is if you don't know how to already .
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