P0B07 code meaning
Electric/Auxiliary Transmission Fluid Pump Motor Phase W Current Low
Powertrain system Generic code P0Bxx codes Check engine light
What P0B07 means
P0B07 means phase W of the auxiliary fluid pump motor carries less current than commanded, the typical sign of an open W path. GM uses it on the Volt and later hybrids: below 1 A peak W-axis current for 0.4 s of 0.6 s, with the inverter in normal PWM above 50 V, sets a Type A fault. A GM service update for the 2017-18 Cadillac CT6 plug-in shows the code had been calibrated off; a W phase loss then shut the car down or prevented starting with no code and no MIL, until reprogramming of the drive motor power inverter module enabled P0B07 as Type A. On the 2014-15 Spark EV, bulletin PI1433 ties P0B01, P0B04 or P0B07 to an unlatched pump connector. P0B01 and P0B04 are phases U and V, P0B08 the high side, P0B06 the general W code.
P0B07 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor0.5 to 6 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0B07
- MIL and Service Vehicle Soon light
- Loss of propulsion, vehicle shutdown or no-start
Common causes of P0B07
- Most likelyPump motor connector not fully seated or latched (Chevrolet Spark EV)
- PossibleOpen circuit in the phase W lead or terminal
- PossibleOutdated inverter software (Cadillac CT6 plug-in, service update 18199)
- Less likelyOpen winding of phase W in the pump motor
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Aux trans pump motor phase wAux trans pump control moduleWiring harness
What each part of P0B07 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| B | Area: hybrid propulsion. |
| 07 | The exact fault in that area. |
What to do next
- Note P0B07 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 P0B07
What does P0B07 mean?
P0B07 means "Electric/Auxiliary Transmission Fluid Pump Motor Phase W Current Low". P0B07 means phase W of the auxiliary fluid pump motor carries less current than commanded, the typical sign of an open W path. It is a generic code, so it means the same on every make.
Is it safe to drive with P0B07?
Drive gently and only to a workshop. With P0B07 the car can go into limp mode (reduced power) to protect itself.
Will P0B07 fail an emissions test?
Yes, it can. P0B07 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 P0B07 to fix?
Difficulty: hard. A typical repair takes 0.5 to 6 hours of work. This is a job for a workshop.
Will P0B07 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.