P0892 TCM Power Relay Sense Circuit Intermittent

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. P0892 reports a sense signal that drops out now and then, from a loose contact in relay, socket or wiring. Brief supply interruptions can reboot the module (compare P0884) and cause shift shocks. No maker publishes a strategy.

Likely causes

Symptoms

• Sporadic gearbox warning
• Brief limp mode or shift shock

Repair estimate

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

Related codes

References: law.cornell.edu, static.nhtsa.gov.