P06B2

What it means

P06B2 means the engine control module has detected a voltage that is too high on sensor power supply circuit A, which is the regulated reference voltage (usually 5 volts) it supplies to a group of sensors. The module monitors this supply and sets the code when it reads above the expected range. Which sensors share supply A depends on the vehicle and engine.

Symptoms

• Engine warning light on
• Reduced power or limp mode
• Poor or erratic throttle response
• Rough running or hesitation
• Hard starting or no start
• Other sensor fault codes stored at the same time

Possible causes

• Short to a higher voltage (such as battery positive) in the sensor supply wiring or a shared sensor connectorlikely
• Faulty sensor sharing supply A that is pulling the reference voltage highpossible
• Damaged wiring, chafed loom or water-contaminated connector causing cross-connection between circuitslikely
• Poor or open sensor ground return causing the supply reading to risepossible
• Fault in the engine control module's internal voltage regulatorrare
• Previous poor repair or aftermarket wiring interfering with the sensor circuitspossible

How to diagnose

1. Read all stored and pending codes and note any other sensor circuit faults, as these help identify which sensors share supply A
2. Review freeze frame data to see engine speed, load and temperature when the code set
3. Check the wiring diagram for the specific model and engine to identify which sensors share supply A
4. Visually inspect the related wiring, loom routing and connectors for chafing, corrosion, water ingress, bent pins or signs of previous repairs
5. With the ignition on, measure the reference voltage at the sensor connectors and compare it with the specified value
6. Unplug the shared sensors one at a time while monitoring the supply voltage to see if a particular sensor causes the fault
7. Check for a short to battery voltage and check the sensor ground circuits for resistance, with the control module disconnected as the procedure requires
8. If wiring and sensors test good, check the module's power and ground supplies and consider the module itself, following the manufacturer's procedure

How to fix

• Repair or replace damaged wiring and fix any short to a higher voltage
• Clean or replace corroded or damaged connectors and terminals
• Replace the faulty sensor that is pulling the supply voltage high
• Repair poor sensor ground connections
• Replace or repair the engine control module only after all other causes are ruled out, then complete any required programming

Can I keep driving?

Nearby codes

• P06B1GenericSensor Power Supply A Circuit Low
• P06B3GenericSensor Power Supply B Circuit/Open