P0637 indicates the vehicle's control module has detected a voltage signal in the power steering control circuit that exceeds the normal operating range. This electrical fault typically resides in the wiring harness, connectors, or the steering assist components themselves. Driving may be affected if steering assist is reduced or disabled due to the error.
Damaged insulation allowing the control circuit wire to contact a voltage source is the most common trigger for high voltage codes.
Internal electrical failures within the assist motor or pump can send erroneous high voltage signals to the controller.
Oxidation or loose pins at the steering module connectors can disrupt signal integrity and cause voltage spikes.
The dedicated module managing steering assist may have internal circuitry faults causing incorrect voltage regulation.
Poor grounding points can cause voltage reference issues that mimic high circuit voltage readings.
Computer failure is extremely rare and should only be considered after all wiring and components are verified functional.
No, PCM failure is very uncommon for this code; wiring and steering components are the probable causes.
Caution is advised because power steering assist may be reduced or fail suddenly, making the vehicle harder to control.
No, clearing the code only resets the warning light temporarily without repairing the underlying electrical fault.
No, this is an electrical circuit code; low fluid typically triggers pressure or mechanical performance codes.