P2551: Torque Management Request Input Signal B Circuit High
What to do
The car will probably feel normal or slightly livelier, with harsher gearchanges as the main clue. What has been lost is the ability of the traction and stability systems to cut power quickly, which counts on a wet or loose surface. The usual finding is a connector rather than an expensive part.
What this code means
The second torque management request circuit reads above its valid range — an open circuit, a disconnected connector, or a short to supply.
As on the A circuit at P2547, an open line means the request can never arrive. The engine makes full power and the loss shows up only where the reduction was doing work: harsher gearchanges, and a traction control system left with brakes alone. Nothing feels broken and something has gone.
Likely causes
Start here
- Open circuit in sensor wiring · moderate
- Corroded or loose connector · easy
- Disconnected sensor connector · easy
Less common
- Wiring shorted to voltage · moderate
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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