P0C56: Drive Motor B Position Sensor Circuit A Range/Performance

P0C56 flags a plausibility problem on Circuit A of the motor B resolver: the winding is connected and its level sits inside the electrical window, yet the signal it carries does not fit, for instance because it wanders or no longer matches the second winding. No manufacturer documents this code publicly. The closest published case is the motor A version P0C51, which Bentley traces to connector pin fit and contamination on its 2025 Continental hybrids. Possible reasons on motor B are the same kind of contact issue, a resolver with weakened output or interference on poorly shielded lines. P0C57 to P0C59 cover hard low, high and sporadic faults, and P0A46 judges the overall motor B angle signal.

Symptoms

• Hybrid warning and check engine lamp
• Motor B torque limited or switched off
• Occasional shudder when motor B takes load

Most likely causes

• Poor pin fit or contamination at the motor B resolver connector
• Damaged shield or twisted pair letting interference onto Circuit A
• Motor B resolver winding with weakened output

What to check, in order

Start with the simplest. You can tick off each step.

1. Read the codes with a hybrid-compatible scanner and write down the freeze frame data
2. Compare the reading with other engine data while varying the engine speed.
3. Make sure the battery cooling air intake is clean
4. Check the 12 V auxiliary battery, which can also trigger warnings
5. Leave any high-voltage measurements to a specialized repair shop

Good to know

• It can trigger limp mode.
• It affects emissions.

What each character of P0C56 means

• P: Powertrain: engine and transmission
• 0: Generic code: same on every make
• C: Subsystem depends on the code range
• 56: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0C56?

If the car still runs, drive as little as possible and go to a specialized repair shop. Do not touch the orange cables: they carry high voltage.

What causes code P0C56?

The most common causes are: poor pin fit or contamination at the motor B resolver connector; damaged shield or twisted pair letting interference onto Circuit A; motor B resolver winding with weakened output.

Related codes

• P0C55Drive Motor B Position Sensor Circuit A
• P0C57Drive Motor B Position Sensor Circuit A Low
• P0C58Drive Motor B Position Sensor Circuit A High
• P0C59Drive Motor B Position Sensor Circuit A Intermittent/Erratic
• P0C60Drive Motor B Position Sensor Circuit B Range/Performance
• P0A46Drive Motor B Position Sensor Circuit Range/Performance

Sources

• law.cornell.edu: 13 CCR 1968.2
• static.nhtsa.gov: MC 11027863 0001
• en.wikipedia.org: Resolver (electrical)

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.