OBD-II code · Powertrain (generic, extended)
P2543 Power Demand Signal Circuit
The ECU detects an electrical fault on the power demand input signal used to coordinate accessory loads (e.g. AC compressor, alternator load). The signal is missing or implausible.
Is it safe to drive with P2543?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyOpen signal wire
- PossibleFault in requesting module
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.3–1.5 h
- Emissions test
- Usually unaffected
- Parts involved
- Power Demand Signal Module, HVAC Module
Related codes
- P2540Low Pressure Fuel System Sensor Circuit
- P2541Low Pressure Fuel System Sensor Circuit Range/Performance
- P2542Low Pressure Fuel System Sensor Circuit High
- P2544Torque Management Request Input Signal A
- P2545Torque Management Request Input Signal A Range/Performance
- P2546Torque Management Request Input Signal A Low
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.