P0890 code meaning
TCM Power Relay Sense Circuit Low
Powertrain system Generic code P08xx codes Check engine light
What P0890 means
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. P0890 means the relay delivers no voltage despite the command. Subaru documents it in four bulletins from 2022 to 2025 (Ascent, WRX, Impreza, Crosstrek, Forester): after a short trip below 0 °C condensation freezes the ignition relay contacts, the starter does not crank and P0700 often comes along. Engine module software cycles the contacts; the 2025 Forester also gets a vented relay.
P0890 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyEasy
- Typical labor0.3 to 1.5 hours
- Clears after repairAfter a drive cycle
Symptoms of P0890
- Starter does not crank after a short trip in frost (Subaru)
- MIL on, P0700 in the engine module
- False oil level or other warnings
Common causes of P0890
- Most likelyRelay contacts frozen or corroded (Subaru ignition relay)
- Most likelyOutdated engine module software (Subaru)
- PossibleFuse or wire between relay and gearbox module
- Less likelyWeak battery
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Transmission relayRelay wiringFuseTransmission control module
What each part of P0890 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 8 | Area: transmission. |
| 90 | The exact fault in that area. |
What to do next
- Note P0890 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0890
What does P0890 mean?
P0890 means "TCM Power Relay Sense Circuit Low". Some gearboxes draw their power through a relay, such as the transmission control relay in Chrysler's fuse box that feeds the solenoids. It is a generic code, so it means the same on every make.
Is it safe to drive with P0890?
Drive gently and only to a workshop. With P0890 the car can go into limp mode (reduced power) to protect itself.
Will P0890 fail an emissions test?
Yes, it can. P0890 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0890 to fix?
Difficulty: easy. A typical repair takes 0.3 to 1.5 hours of work. This is a job for a workshop.
Will P0890 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.