Code result
P2543
Power Demand Signal Circuit
Moderate severity
What it means
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?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Open signal wire
highOne of the most commonly reported causes for this code — check this first.
Fault in requesting module
mediumA plausible cause — test and verify before replacing parts.
Related help
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