DTC P066A
Diagnostic Instructions
DTC Descriptor
DTC P066A 00: Cylinder 1 Glow Plug Control Circuit Low Voltage
Circuit/System Description
This DTC applies to internal microprocessor integrity conditions within the glow plug control module.
Conditions for Running the DTC
• | The battery voltage is between 9-16 V. |
• | The DTC runs once per ignition cycle when the above condition is met. |
Conditions for Setting the DTC
The ECM detects a glow plug control module malfunction.
Action Taken When the DTC Sets
DTC P066A 00 is a Type A DTC.
Conditions for Clearing the DTC
DTC P066A 00 is a Type A DTC.
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Component Connector End Views
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Ignition OFF, disconnect the harness connector at the K34 Glow Plug Control Module.
- Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.
Circuit/System Testing
- Ignition OFF, disconnect the harness connectors at the K34 Glow Plug Control Module.
- Test for less than 5 Ω of resistance between the ground circuit terminal 3 X1 and ground.
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
- Test for greater than 0.3 Ω of resistance between each of the glow plug circuit terminals and ground.
• | E12A Glow Plug 1 circuit terminal 3 X2 |
• | E12B Glow Plug 2 circuit terminal 1 X2 |
• | E12C Glow Plug 3 circuit terminal 4 X2 |
• | E12D Glow Plug 4 circuit terminal 6 X2 |
⇒ | If less than the specified range, test the glow plug circuit for a short to ground. If the circuit tests normal, replace the appropriate Glow Plug. |
- Ignition ON, verify a test lamp illuminates between the K34 Glow Plug Control Module ignition voltage circuit terminal 4 X1 and ground.
⇒ | If the test lamp does not illuminate, test the ignition voltage circuit for a short to ground or an open/high resistance. |
- If all circuits test normal, replace the K34 Glow Plug Control Module.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
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