P0A8D code meaning
14 Volt Power Module System Voltage Low
Powertrain system Generic code P0Axx codes Check engine light
What P0A8D means
P0A8D reports too low a voltage at the 14 V power module (DC/DC converter feeding the 12 V network). GM uses it in its 2013 eAssist tables as the circuit-low check of the APM low-voltage sensor: if that sensor reads below 1 V for 1.5 s within a 2 s window while ignition voltage is 9 to 32 V, the code sets; it passes again above 1.5 V. It is Type B, two trips to MIL. Because a real 12 V network cannot be at 1 V with the ignition on, GM's version really points to an open or shorted voltage sense line or a failed sensor, not a flat battery. Other makers may apply the code to genuine undervoltage. P0A8E is the high counterpart, P0A8F the correlation check.
P0A8D at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyWorkshop only
- Typical labor1 to 4 hours
- Clears after repairAfter a drive cycle
Symptoms of P0A8D
- MIL and charging/hybrid warning
- 12 V battery discharges
- Start/stop disabled
Common causes of P0A8D
- Most likelyVoltage sense line open or shorted to ground
- PossibleVoltage sensor inside the power module failed
- Less likelyConverter not delivering output (fuse, output cable)
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Pm14v moduleDcdc converter
What each part of P0A8D means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| A | Area: hybrid propulsion. |
| 8D | The exact fault in that area. |
What to do next
- Note P0A8D and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0A8D
What does P0A8D mean?
P0A8D means "14 Volt Power Module System Voltage Low". P0A8D reports too low a voltage at the 14 V power module (DC/DC converter feeding the 12 V network). It is a generic code, so it means the same on every make.
Is it safe to drive with P0A8D?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P0A8D fail an emissions test?
Yes, it can. P0A8D is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0A8D to fix?
Difficulty: workshop only. A typical repair takes 1 to 4 hours of work. This is a job for a workshop.
Will P0A8D clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.