Some gearboxes draw their power through a relay, such as the transmission control relay in Chrysler's fuse box that feeds the solenoids. P0885 to P0887 cover the coil control of that relay, P0888 to P0892 its sense line, which reads back the switched output and compares it with the command. A dead relay leaves all solenoids without power, so the gearbox drops into its hydraulic emergency gear. P0889 means the read-back voltage does not fit the switching state or the system voltage: clearly below battery voltage, a voltage drop across the contact or a delayed drop-out. No maker publishes a strategy.
Medium severity. Can I keep driving?It depends on the symptoms. If the car is running normally you can go to a repair shop; if it goes into limp mode, drive as little as possible.
Symptoms
- MIL or gearbox warning
- Occasional limp mode
Most likely causes
- Relay contact with high resistance
- Moisture or corrosion in relay or socket
- Ground or supply problem
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: easy
- It can trigger limp mode.
- It affects emissions.
What each character of P0889 means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 8: Transmission
- 89: Specific fault in that system
Frequently asked questions
Can I keep driving with code P0889?
It depends on the symptoms. If the car is running normally you can go to a repair shop; if it goes into limp mode, drive as little as possible.
What causes code P0889?
The most common causes are: relay contact with high resistance; moisture or corrosion in relay or socket; ground or supply problem.
Related codes
- P0888TCM Power Relay Sense Circuit
- P0890TCM Power Relay Sense Circuit Low
- P0891TCM Power Relay Sense Circuit High
- P0892TCM Power Relay Sense Circuit Intermittent
Sources
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.