Hummer H3. Manual — part 1137

3

System Check -
Vehicle

Go to Step 4

4

1. Install a scan tool.

2. Turn ON the ignition, with the engine

OFF.

3. With a scan tool, observe the Crank

Request Signal parameter in the
powertrain control module (PCM)
data list.

4. Turn the ignition switch to the

START position.

Does the scan tool display Yes?

Go to Step 5

Go to Power

Mode

Mismatch

5

1. Turn ON the ignition, with the engine

OFF.

2. With a scan tool, observe the Starter

Relay Command parameter in the
PCM data list.

3. Turn the ignition switch to the

START position.

Does the scan tool display Yes?

Go to Step 7

Go to Step 6

6

1. Turn ON the ignition, with the engine

OFF.

2. Verify that the transmission is in Park

or Neutral.

3. With a scan tool, observe the TR Sw.

parameter in the PCM data list.

Does the scan tool display Park or
Neutral?

Go to Step 7

Go to Range
Selector
Displays
Incorrect Range

7

Turn the ignition switch to the START
position.
Do you hear the PCM CNTRL relay click?

Go to Step 10

Go to Step 8

1. Turn OFF the ignition.

2. Disconnect the PCM CNTRL relay.

2007 Hummer H3

2007 ENGINE Engine Electrical - H3

8

3. Turn ON the ignition, with the engine

OFF.

4. Connect a test lamp between the

battery positive voltage circuit of the
PCM CNTRL relay coil and a good
ground.

Does the test lamp illuminate?

Go to Step 9

Go to Step 18

9

1. Connect a test lamp between the

battery positive voltage circuit of the
PCM CNTRL relay coil and the
control circuit of the PCM CNTRL
relay.

2. Turn the ignition to the START

position.

Does the test lamp illuminate?

Go to Step 15

Go to Step 14

10

1. Turn OFF the ignition.

2. Disconnect the PCM CNTRL relay.

3. Connect a test lamp between the

battery positive voltage circuit of the
PCM CNTRL relay switch and a
good ground.

Does the test lamp illuminate?

Go to Step 11

Go to Step 19

11

Connect a 30-amp fused jumper between
the battery positive voltage circuit of the
PCM CNTRL relay switch and the starter
solenoid crank voltage circuit.Does the
engine crank?

IMPORTANT:

Ensure the parking brake is applied and the
transmission is in park if equipped with an
automatic transmission or neutral on a manual
transmission.

Go to Step 16

Go to Step 12

12

Does the fuse in the jumper open?

Go to Step 20

Go to Step 13

Test the starter solenoid crank voltage

2007 Hummer H3

2007 ENGINE Engine Electrical - H3

13

circuit for a high resistance or open. Refer
to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?

Go to Step 24

Go to Step 16

14

Test the control circuit of the PCM
CNTRL relay for an open or short to
battery voltage. Refer to Circuit Testing
and Wiring Repairs .
Did you find and correct the condition?

Go to Step 24

Go to Step 17

15

Inspect for poor connections at the PCM
CNTRL relay. Refer to Testing for
Intermittent Conditions and Poor
Connections and Connector Repairs .
Did you find and correct the condition?

Go to Step 24

Go to Step 21

16

Inspect for poor connections at the starter
solenoid. Refer to Testing for
Intermittent Conditions and Poor
Connections and Connector Repairs .
Did you find and correct the condition?

Go to Step 24

Go to Step 22

17

Inspect for poor connections at the harness
connector of the PCM. Refer to Testing
for Intermittent Conditions and Poor
Connections and Connector Repairs .
Did you find and correct the condition?

Go to Step 24

Go to Step 23

18

Repair an open or high resistance in the
battery positive voltage circuit of the PCM
CNTRL relay coil. Refer to Wiring
Repairs .
Did you complete the repair?

Go to Step 24

-

19

Repair the open or high resistance in the
battery positive voltage circuit of the PCM
CNTRL relay switch. Refer to Wiring
Repairs .
Did you complete the repair?

Go to Step 24

-

20

Repair the short to ground in the starter
solenoid crank voltage circuit. Refer to
Wiring Repairs .
Did you complete the repair?

Go to Step 24

-

Replace the PCM CNTRL relay. Refer to

2007 Hummer H3

2007 ENGINE Engine Electrical - H3

STARTER SOLENOID CLICKS, ENGINE DOES NOT CRANK

Starter Solenoid Clicks, Engine Does Not Crank

21

Relay Replacement (Attached to Wire
Harness) or Relay Replacement (Within
an Electrical Center) .
Did you complete the replacement?

Go to Step 24

-

22

Replace the starter motor. Refer to Starter
Motor Replacement.
Did you complete the replacement?

Go to Step 24

-

23

Replace the PCM. Refer to Control
Module References for replacement,
setup and programming.
Did you compete the replacement?

Go to Step 24

-

24

Operate the system in order to verify the
repair.
Did you correct the condition?

System OK

Go to Step 2

Step

Action

Yes

No

Schematic Reference: Starting and Charging Schematics

1

Did you perform the Diagnostic System
Check - Vehicle?

Go to Step 2

Go to
Diagnostic
System Check -
Vehicle

2

Turn the ignition to the START position.
Did the starter solenoid click?

Go to Step 3

Go to Starter
Solenoid Does
Not Click

3

Inspect the engine and belt drive system for
mechanical binding, e.g. seized engine,
seized generator.
Does the engine move freely?

Go to Step 4

Go to Engine
Will Not Crank
- Crankshaft
Will Not Rotate

4

Test the battery positive cable between the
battery and the starter solenoid for high
resistance. Refer to Circuit Testing and
Wiring Repairs .
Did you find and correct the condition?

Go to Step 8

Go to Step 5

Test the ground circuit between the battery
and the starter motor for a high resistance.

2007 Hummer H3

2007 ENGINE Engine Electrical - H3