The P0885: TCM Power Relay Control Circuit/Open refers to a problem where the transmission control module (TCM) power relay control circuit is open, meaning there is a break in the circuit. This can prevent the TCM from receiving the necessary power to control transmission operations properly, leading to transmission performance issues.
P0885 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P0885: TCM Power Relay Control Circuit/Open |
| Is it serious? | Yes, this can lead to transmission control failure, potentially resulting in the vehicle failing to shift properly or not starting. |
| Possible causes | – Open circuit in the TCM power relay control circuit – Faulty TCM power relay – Wiring or connector issues |
| How to diagnose? | – Test the TCM power relay control circuit – Inspect wiring and connectors – Replace faulty components if needed |
P0885 Meaning
The P0885 code indicates that there is an open circuit in the power relay control circuit for the transmission control module (TCM). This could be due to a faulty relay, broken wiring, or disconnected connectors, which prevent the TCM from controlling the transmission properly. If the TCM cannot power up, the vehicle may have shifting issues or may not start at all.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for any additional codes that may provide further insight into the issue. | OBD-II Scanner |
| Inspect Wiring and Connectors | Visually inspect the wiring and connectors in the TCM power relay control circuit for any damage, corrosion, or disconnections. | Flashlight, Multimeter |
| Test TCM Power Relay Control Circuit | Use a multimeter to test the TCM power relay control circuit for continuity and proper operation. | Multimeter, Vehicle Manual |
| Check the TCM Power Relay | Test the TCM power relay to ensure it is functioning correctly. If it is faulty, replace it with a new one. | Multimeter, Replacement Relay |
| Replace Faulty Components | Replace any faulty wiring, connectors, or relays identified during the inspection. | Replacement parts, Tools |
| Clear Code and Test Drive | After making necessary repairs, clear the code and take the vehicle for a test drive to confirm that the issue has been resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
| Recheck for Codes | Re-scan the vehicle after the test drive to ensure the P0885 code has not returned. | OBD-II Scanner |
OBD-II scanner Buyer’s Guide
- Scanner features explained
- Different types of scanners
- Scanners for coding/odometer/ECU/checks
- Best picks + discount codes
I test OBD-II scanners and make DIY Engine diagnostics guides to help you solve your car problems without having to depend on the mechanic. A lot of them will try to scam you or are just no help at all. About Juraj Lukacko