The P068F: Cylinder 8 Glow Plug Control Circuit High code indicates that the control module has detected a higher-than-expected voltage in the glow plug control circuit for cylinder 8. This elevated voltage can prevent the glow plug from functioning properly and may cause engine starting issues, especially in cold weather. The issue could be due to a faulty glow plug, wiring problems, or a malfunction in the control circuit.
P068F – Quick Overview
| Code | Information |
|---|---|
| Meaning | P068F: Cylinder 8 Glow Plug Control Circuit High |
| Is it serious? | Yes, as high voltage can damage the glow plug and cause engine starting issues. |
| Possible causes | – High voltage in the cylinder 8 glow plug control circuit – Faulty glow plug – Wiring issue |
| How to diagnose? | – Test cylinder 8 glow plug control circuit for voltage – Inspect wiring and connectors – Replace glow plug if necessary |
P068F Meaning
The P068F code means that the control module has detected higher-than-expected voltage in the glow plug control circuit for cylinder 8. This high voltage can prevent the glow plug from heating properly or damage the plug, leading to engine starting problems, particularly in cold conditions.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for additional related codes, particularly those concerning the glow plug system or electrical faults. | OBD-II Scanner |
| Test the Cylinder 8 Glow Plug Control Circuit for Voltage | Use a multimeter to measure the voltage in the glow plug control circuit for cylinder 8. Compare the readings with the manufacturer’s specifications to verify if the voltage is too high. | Multimeter |
| Inspect Wiring and Connectors | Inspect the wiring and connectors leading to cylinder 8’s glow plug for signs of damage, corrosion, or loose connections that could cause high voltage. | Flashlight, Multimeter |
| Test the Glow Plug for Cylinder 8 | Test the glow plug in cylinder 8 to ensure it is functioning correctly and not damaged by excessive voltage. Replace the glow plug if necessary. | Diagnostic Tool, Multimeter |
| Replace the Glow Plug if Necessary | If the glow plug for cylinder 8 is faulty or damaged due to high voltage, replace it to restore proper engine starting performance. | Replacement Glow Plug, Tools |
| Clear the Code and Test | After repairs, clear the code using an OBD-II scanner and test the vehicle to ensure the cylinder 8 glow plug control circuit is functioning correctly. | OBD-II Scanner, Vehicle Manual |
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