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Home >> Hummer >> 2005 >> H2 4D Utility Pickup >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Troubleshooting >> Troubleshooting >> Malfunction Indicator Lamp (MIL) Inoperative >> Test Description
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Test Description

The number below refers to the step number on the diagnostic table.

  1. 4:  This step tests for a short to voltage on the MIL control circuit. With the fuse removed there should be no voltage on the MIL control circuit.
Malfunction Indicator Lamp (MIL) Inoperative

Step Action Values Yes No
Schematic Reference: Instrument Cluster Schematics in Instrument Panel, Gages, and Console or Engine Controls Schematics
Connector End View Reference: Instrument Panel, Gages, and Console Connector End Views in Instrument Panel, Gages, and Console or Powertrain Control Module (PCM) Connector End Views
1 Did you perform the Diagnostic System Check - Vehicle? - Go to Step 2  Go to Diagnostic System Check - Vehicle
2 Command the malfunction indicator lamp (MIL) ON and OFF with a scan tool.
Does the MIL turn ON and OFF when commanded with a scan tool?
- Go to Testing for Intermittent Conditions and Poor Connections Go to Step 3 
3 Inspect the fuse that supplies voltage to the MIL.
Is the fuse open?
- Go to Step 11  Go to Step 4 
  1. Turn OFF the ignition.
  2. Remove the fuse that supplies voltage to the MIL.
  3. Disconnect the powertrain control module (PCM).
  4. Turn ON the ignition with the engine OFF.
  5. Measure the voltage from the MIL control circuit in the PCM harness connector to a good ground.
Is the voltage less than the specified value?
0.3 V Go to Step 5  Go to Step 10 
5
  1. Turn OFF the ignition.
  2. Install the fuse that supplies voltage to the MIL.
  3. Turn ON the ignition with the engine OFF.
  4. Connect a 3-amp fused jumper wire between the MIL control circuit in the PCM harness connector and a good ground.
Is the MIL illuminated?
- Go to Step 9  Go to Step 6 
6
  1. Turn OFF the ignition.
  2. Remove the instrument panel cluster (IPC). Refer to Instrument Panel Cluster (IPC) Replacement .
  3. Turn ON the ignition, with the engine OFF.
  4. Probe the MIL voltage supply circuit of the IPC harness connector with a test lamp that is connected to a good ground.
Does the test lamp illuminate?
- Go to Step 7  Go to Step 12 
7 Test the MIL control circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct a condition?
- Go to Step 15  Go to Step 8 
8 Test for an intermittent and for a poor connection at the IPC. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .
Did you find and correct the condition?
- Go to Step 15  Go to Step 13 
9 Test for an intermittent and for a poor connection at the PCM. Refer to Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .
Did you find and correct the condition?
- Go to Step 15  Go to Step 14 
10 Repair the short to voltage in the MIL control circuit. Refer to Wiring Repairs .
Did you complete the repair?
- Go to Step 15  -
11 Repair the short to ground in the voltage supply circuit. Refer to Wiring Repairs .
Did you complete the repair?
- Go to Step 15  -
12 Repair the open in the MIL voltage supply circuit. Refer to Wiring Repairs .
Did you complete the repair?
- Go to Step 15  -
13 Replace the IPC. Refer to Instrument Panel Cluster (IPC) Replacement .
Did you complete the replacement?
- Go to Step 15  -
14 Replace the PCM. Refer to Control Module References for replacement, setup, and programming.
Did you complete the replacement?
- Go to Step 15  -
15 Command the MIL ON and OFF with a scan tool.
Does the MIL turn ON and OFF when commanded with a scan tool?
- Go to Step 16  Go to Step 2 
16 Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?
- Go to Diagnostic Trouble Code (DTC) List - Vehicle System OK