The glow relay is controlled by the engine control module (ECM). When the ECM detects engine coolant temperature is less than 10 degrees, the ECM turns ON the glow relay. If the ECM detects an open or short circuit at the glow relay control circuit, this DTC will set.
This diagnostic procedure supports the following DTC:
DTC P0382 Glow Plug Feedback Circuit
• | The ignition switch is ON. |
• | The battery voltage is between 10-16 volts. |
• | The ECM detects a low voltage condition on the glow relay control circuit for longer than 5 seconds when the glow relay is commanded OFF. |
• | The ECM detects a high voltage condition on the glow relay control circuit for longer than 5 seconds when the glow relay is commanded ON. |
• | The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. |
• | The ECM records the operating conditions at the time the diagnostic fails. The ECM stores this information in the Failure Records. |
• | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
• | Clear the MIL and the DTC with a scan tool. |
• | If an intermittent condition is suspected, the following may cause an intermittent: |
- | Poor connections |
- | A misrouted harness |
- | Rubbed through wire insulation |
- | Broken wire inside the insulation |
• | Inspect for the following conditions: |
- | Poor connection at ECM--Inspect the harness connectors for the following conditions: |
• | Backed-out terminals |
• | Improper mating |
• | Broken locks |
• | Improperly formed or damaged terminals |
• | Poor terminal to wire connection |
- | Damaged harness--Inspect the wiring harness for damage. If the harness appears to be OK, observe the Engine Coolant Temperature display on the scan tool while moving the connectors and the wiring harness related to the sensor. A change in the display will indicate the location of the fault. |
Step | Action | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | |||||||||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |||||||
2 |
Did the DTC fail this ignition? | Go to Step 3 | Go to Diagnostic Aids | ||||||
3 |
Did you find and correct the condition? | Go to Step 7 | Go to Step 4 | ||||||
4 |
Did you find and correct the condition? | Go to Step 7 | Go to Step 5 | ||||||
5 |
Did you find and correct the condition? | Go to Step 7 | Go to Step 6 | ||||||
6 |
Important: The new ECM must be programmed. Replace the ECM. Refer to Engine Control Module Programming and Setup , Engine Control Module Replacement/Restore Fuel Rate Data , and Fuel Injector Flow Rate Programming . Did you complete the replacement? | Go to Step 7 | -- | ||||||
7 |
Did the DTC fail this ignition? | Go to Step 2 | Go to Step 8 | ||||||
8 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | System OK |