The P099C: Shift Solenoid ‘G’ Control Circuit High refers to a high voltage issue in the control circuit of shift solenoid ‘G’. This can be caused by a faulty solenoid, excessive voltage supply, or wiring/connector issues, which can affect the transmission’s shifting performance.
P099C – Quick Overview
| Code | Information |
|---|---|
| Meaning | P099C: Shift Solenoid ‘G’ Control Circuit High |
| Is it serious? | Yes, this issue can cause erratic shifting or transmission malfunction. |
| Possible causes | – High voltage in the shift solenoid ‘G’ control circuit – Faulty shift solenoid ‘G’ – Wiring or connector issues |
| How to diagnose? | – Check the circuit for high voltage – Inspect wiring and connectors – Replace the shift solenoid ‘G’ if necessary |
P099C Meaning
The P099C code indicates that the shift solenoid ‘G’ is receiving a higher voltage than expected. This can lead to transmission shifting issues or other performance problems. The issue may arise due to faulty wiring, connectors, or a malfunctioning solenoid.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for additional transmission-related codes. | OBD-II Scanner |
| Inspect Shift Solenoid ‘G’ | Visually inspect the shift solenoid ‘G’ for any visible damage or malfunction. | Flashlight, Safety Gloves |
| Test the Circuit for High Voltage | Use a multimeter to test the voltage in the shift solenoid ‘G’ control circuit. | Multimeter |
| Inspect Wiring and Connectors | Check the wiring and connectors for signs of wear, shorts, or corrosion. | Flashlight, Multimeter |
| Replace Shift Solenoid ‘G’ | Replace the shift solenoid ‘G’ if it is found to be faulty. | Replacement Parts (Solenoid) |
| Clear the Code and Test Drive | After repairs, clear the code and take the vehicle for a test drive. | OBD-II Scanner, Vehicle Manual |
| Recheck for Codes | Re-scan the system to confirm the P099C code has been resolved. | OBD-II Scanner |
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