P2546 Torque Management Request Input Signal A Low

P2546 says that torque request A, the channel over which one module asks another to raise or cut engine torque, reads below its permitted floor. On a hard-wired request this points to a line pulled toward ground; on a data-bus request it means a value pinned at or under the minimum the receiver accepts. Jaguar is the clearest user: SSM73594 (December 2017) covers the 2018MY E-Pace with the ZF 9HP48 nine-speed, whose transmission module stores P2546-86, sometimes together with P2545-86, while the root cause was still being investigated. The dealer sequence is leak check, oil level, newer TCM software, then clear and only call technical assistance if it returns; Land Rover issued a matching note, SSM73291, for its own 9HP48 models. P2547 is the high-side counterpart. Drivers may notice rough or delayed shifts.

Likely causes

Symptoms

• Harsh or delayed gear changes
• Transmission warning message or check engine light
• Fault often stored together with P2545

Repair estimate

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

Parts involved

Related codes

References: static.nhtsa.gov, static.nhtsa.gov.