The P0626: Generator Field/F Terminal Circuit High code indicates that the vehicle’s control module has detected excessively high voltage in the generator field (or F terminal) circuit. This may result from a faulty generator field terminal, high voltage supply, or wiring problems that can affect the vehicle’s charging system.
P0626 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P0626: Generator Field/F Terminal Circuit High |
| Is it serious? | Yes, as it may indicate issues with the charging system. |
| Possible causes | – Faulty generator field/F terminal – High voltage in circuit – Wiring issue |
| How to diagnose? | – Test generator field/F terminal for high voltage – Inspect wiring and connectors – Replace generator field/F terminal if necessary |
P0626 Meaning
The P0626 code indicates that the generator field (F terminal) circuit is experiencing higher-than-expected voltage. The generator field terminal controls the alternator’s output, and if it detects a high voltage, it can cause charging system malfunctions. This can result in overcharging of the battery, which may lead to further electrical issues.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for additional codes related to the charging system, as they might help pinpoint the issue. | OBD-II Scanner |
| Test the Generator Field/F Terminal for High Voltage | Use a multimeter to measure the voltage at the generator field (F terminal) to determine if it is within the correct range. | Multimeter |
| Inspect Wiring and Connectors | Inspect the wiring and connectors associated with the generator field/F terminal for damage, loose connections, or corrosion. | Flashlight, Multimeter |
| Test the Generator (Alternator) | If necessary, test the generator or alternator to verify it is functioning properly and not contributing to the high voltage. | Diagnostic Tool, Multimeter |
| Replace the Generator Field/F Terminal if Necessary | If the field terminal is faulty or contributing to the high voltage, replace it to restore proper voltage control in the charging system. | Replacement Terminal, Tools |
| Clear the Code and Test | After completing repairs, clear the code using an OBD-II scanner and test the vehicle to ensure the charging system functions properly. | OBD-II Scanner, Vehicle Manual |
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