P0A40 code meaning
Drive Motor A Position Sensor Circuit Range/Performance
Powertrain system Generic code P0Axx codes Check engine light
What P0A40 means
P0A40 means the resolver of motor A still delivers a signal, but its quality is poor or implausible. GM calls this a degraded signal: the sine or cosine value exceeds 4.0 V, judged within 0.2 to 0.4 s of a 2 s window (Type A, one trip in 2016; Type B, two trips on the 2013 mild hybrid). Mitsubishi (2023 Outlander PHEV front motor) sets it when sine or cosine leaves the 2.1 to 2.9 V band for 0.17 s. Audi lists P0A4000 with an implausible signal on the A7 and Q5 e quattro and replaces rotor position sensor G713 after checking gold-plated connector pins; Bentley pairs it with P0C5100/P0C5B00 and inspects connectors for pin drag. P0A3F is the hard signal loss. Expect a drive system warning or no start.
P0A40 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1.5 to 10 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0A40
- Drive system fault message in the instrument cluster
- Vehicle cannot be started or will not enter ready mode
- Electric drive disabled or torque jerks while driving
Common causes of P0A40
- Most likelyRotor position sensor (resolver) delivering a degraded signal, e.g. Audi G713
- Most likelyWorn, loose or contaminated contacts in the resolver connectors (Audi, Bentley)
- PossibleSensor wires pinched or misrouted on the gearbox housing after a repair
- Less likelyFaulty resolver evaluation in the inverter/motor control module
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Drive motor aRotor position sensorResolverWiring harness
What each part of P0A40 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. |
| 40 | The exact fault in that area. |
What to do next
- Note P0A40 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 P0A40
What does P0A40 mean?
P0A40 means "Drive Motor A Position Sensor Circuit Range/Performance". P0A40 means the resolver of motor A still delivers a signal, but its quality is poor or implausible. It is a generic code, so it means the same on every make.
Is it safe to drive with P0A40?
Drive gently and only to a workshop. With P0A40 the car can go into limp mode (reduced power) to protect itself.
Will P0A40 fail an emissions test?
Yes, it can. P0A40 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 P0A40 to fix?
Difficulty: workshop only. A typical repair takes 1.5 to 10 hours of work. This is a job for a workshop.
Will P0A40 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.