P0EB4 code meaning
A/C Compressor Motor Phase U Current Sensor Range/Performance
What P0EB4 means
P0EB4 concerns the plausibility of the phase U current reading of an electric A/C compressor. The value is in range but disagrees with what the controller can work out for itself: in a motor fed by three wires the phase currents must add up to roughly zero, and each phase should follow the commanded current pattern. A standing offset or a wrong gain while running are typical findings. No manufacturer documents P0EB4 publicly. GM's 2011 Volt looked for offsets on its compressor phases only with the motor stopped (plus or minus 68 A, older codes P0D7A and P0D7B). A weakening sensor element or inverter board is the usual cause, so the compressor assembly gets replaced. Electrical faults of phase U are P0EB1 to P0EB3.
P0EB4 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyWorkshop only
- Typical labor1 to 5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0EB4
- Compressor runs roughly or noisily before switching off
- Reduced or intermittent cooling
Common causes of P0EB4
- Most likelyOffset or gain drift of the phase U sensor
- PossibleAgeing measurement circuit on the inverter board
- Less likelyWinding fault in the compressor motor distorting the currents
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Ac compressor motor phase u current sensorAc compressor module
What each part of P0EB4 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| B4 | The exact fault in that area. |
What to do next
- Note P0EB4 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 P0EB4
What does P0EB4 mean?
P0EB4 means "A/C Compressor Motor Phase U Current Sensor Range/Performance". P0EB4 concerns the plausibility of the phase U current reading of an electric A/C compressor. It is a generic code, so it means the same on every make.
Is it safe to drive with P0EB4?
P0EB4 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will P0EB4 fail an emissions test?
P0EB4 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is P0EB4 to fix?
Difficulty: workshop only. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will P0EB4 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.