P0A12 Possible Causes
- Faulty DC/DC converter
- DC/DC converter harness is open or shorted
- Poor electrical connection in the DC/DC converter circuit
- Faulty Powertrain Control Module (PCM)
What Does It Mean?
First Diagnose Code P0A12
Check the “Possible Causes” listed above. Visually inspect the wiring harness and related connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
P0A12 Possible Symptoms
Engine light on (or service engine soon warning light)
P0A12 Description
The Powertrain Control Module (PCM) controls the hardwired DC/DC enable signal to turn the DC/DC converter on and off. The DC/DC converter provides feedback to the PCM using the hardwired DC/DC fault signal. The DC/DC fault signal informs the PCM when the converter is not operational or when a fault has occurred.