P055F

Power Steering Control Module Temperature Sensor Circuit Low

P055F is a generic OBD-II powertrain diagnostic trouble code: Power Steering Control Module Temperature Sensor Circuit Low. It is logged by the engine control unit when the powertrain monitor detects that a specific fault threshold has been exceeded — typically resulting in the malfunction-indicator lamp (MIL / check-engine light) being illuminated.

Code
P055F
Group
Powertrain
System
Powertrain
Severity
Warning (MIL on)
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What P055F means

P055F indicates that the ECM or PSCM (Power Steering Control Module) has detected a voltage on the power steering control module internal temperature sensor circuit that is below the expected operating range. Electric power steering systems use an internal temperature sensor to monitor heat buildup in the motor and control electronics, allowing the module to reduce assist when overheating is detected.

A low circuit condition typically means the sensor signal is near zero volts, suggesting a short to ground on the signal line, a failed internal sensor within the module, or loss of the reference voltage supply. Because this sensor is often integrated into the power steering module, it may not be serviceable separately.

When this fault is active, the system may reduce or disable power steering assist as a protective measure, making steering noticeably heavier. Diagnosis should begin with a visual check of the PSCM connector and power/ground supplies before assuming the module has failed. Some calibration or initialization procedures may be required after module replacement.

Common causes

Most-frequently reported root causes when P055F is logged.

  • 1
    Internal temperature sensor failure within the power steering control module.
  • 2
    Short to ground on the temperature sensor signal circuit.
  • 3
    Loss of reference voltage supply to the internal sensor.
  • 4
    Damaged PSCM wiring harness or connector.
  • 5
    Excessive heat causing permanent sensor damage within the module.
  • 6
    Manufacturing defect in the PSCM internal sensor circuit.
  • 7
    Corrosion inside the PSCM connector reducing reference voltage.

Symptoms drivers notice

MIL or EPS warning light illuminated.
Reduced or intermittent power steering assist.
Heavy steering feel, especially at low speeds.
Power steering assist may be fully disabled if the fault is critical.
No other drivability symptoms beyond steering effort.

How to diagnose P055F

A typical diagnostic flow when this code is present.

  1. 1
    Retrieve all stored DTCs from the PSCM and ECM.
  2. 2
    Inspect the PSCM wiring harness connector for damage, corrosion, or loose pins.
  3. 3
    Verify battery voltage and ground quality at the PSCM connector.
  4. 4
    Check for short to ground on the PSCM sensor signal circuit using a DMM.
  5. 5
    Review PSCM live data for temperature sensor reading; a value at minimum scale indicates circuit low.
  6. 6
    If wiring is intact and connector is clean, the fault likely lies within the PSCM itself.
  7. 7
    Consult manufacturer technical service bulletins before replacing the PSCM, as software updates may address false fault conditions.

Related powertrain codes

Frequently asked questions

Is it safe to drive with P055F?

Driving is possible but steering effort will be higher than normal. Avoid situations requiring rapid steering maneuvers until the fault is repaired.

Can I replace just the temperature sensor?

In most applications the temperature sensor is integrated into the PSCM and is not separately replaceable. Module replacement is typically required if the sensor has failed.

Will P055F clear itself if the module cools down?

If the fault was triggered by a genuine overheat event, it may clear once temperatures normalize. A persistent low circuit code will not self-clear and requires electrical diagnosis.

Does P055F affect ABS or traction control?

Generally no. P055F is specific to the power steering system. However, if the vehicle integrates chassis control functions in a shared module, additional codes may appear.

Disabling P055F in software

RaceTune can permanently disable P055F — and any other OBD-II diagnostic trouble code — on every ECU family we support. The monitor is disabled inside the ECU itself, so the fault stops being logged: the warning light stays off and the engine never enters limp mode for this code. The change is tied to your exact software version.

Permanent
The monitor is disabled in the ECU itself — not just cleared. It cannot return.
Tailored to your file
Each patch is matched to your specific software version — never a one-size-fits-all file.
Reversible
The original file is always preserved. Reflash the stock to return the ECU to factory state.

Software modifications affect emissions compliance and are not road-legal in many jurisdictions. RaceTune service files are intended for motorsport, off-road, and export use.

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