GM Service Manual Online
For 1990-2009 cars only

The following test is designed for engines and batteries at normal operating temperature and assumes that no engine symptoms exist which might cause a no-start symptom. The Battery must be in a charged state before doing the diagnosis. Using the test under other conditions could result in misdiagnosis.

Perform the On-Board Diagnostic System Check in order to be certain that no Diagnostic Trouble codes (DTCs) are stored in the VCM/PCM memory. Refer to Driveability and Emissions in Engine. DTCs stored in the VCM/PCM memory may lead to misdiagnosis.

Slow Crank

Step

Test

Value

Yes

No

1

  1. Disconnect the engine Shut off Solenoid Connector (Diesel) or the Ignition Coil Connector (Gasoline).
  2. Ensure that no other engine problems exist which may affect diagnosis. The surface charge will have been removed if the battery was recently charged. Refer to Battery Replacement .
  3. Connect the voltmeter to the positive and negative battery terminals.
  4. Turn the ignition switch to the Start position.

Is the voltage reading greater than 9.6 volts after 15 seconds of cranking?

9.6 Volts

Go to Step 2

Go to Step 4

 

2

Connect the voltmeter from the negative battery terminal to the engine block.

Is the voltage reading greater than 0.5 Volts?

0.5  Volts

Go to Step 6

Go to Step 3

 

3

Connect the voltmeter from the starter solenoid terminal B to BLK (1) wire battery negative.

Is the voltage greater than 9.0 Volts?

9.0 Volts

Go to Step 5

Go to Step 7

 

4

Perform a battery load test. Refer to Battery Load Test .

Does the battery pass the load test?

--

Go to Step 5

--

5

Repair the starter motor.

Is the repair complete?

--

System OK

--

6

Replace the negative battery cable.

Is the replacement complete?

--

System OK

--

7

Clean and Tighten the positive battery terminals and/or replace the positive battery cable.

Is the replacement complete?

--

System OK

--