P2B87
Coolant Pump A Underspeed
The coolant pump A runs below the calibrated minimum speed for the commanded duty. Mechanical resistance high or supply voltage low.
The coolant pump A runs below the calibrated minimum speed for the commanded duty. Mechanical resistance high or supply voltage low.
Common causes
- high
Mechanical load increased (binding)
One of the most commonly reported causes for this code — check this first.
Typical part cost: $220-1100
- medium
Supply voltage low under load
A plausible cause — test and verify before replacing parts.
Typical part cost: $220-1100
See all causes + fix costs
Create a free Wrenchify account to unlock the rest for P2B87.
Unlock causesFree forever · No credit card
First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
Get the full step-by-step diagnosis
Create a free Wrenchify account to unlock the rest for P2B87.
Unlock diagnosisFree forever · No credit card
Related codes
See related trouble codes
Create a free Wrenchify account to unlock the rest for P2B87.
Unlock related codesFree forever · No credit card
Frequently asked questions
What does P2B87 mean?
P2B87 means "Coolant Pump A Underspeed". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P2B87?
mechanical load increased (binding); supply voltage low under load — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.
Get the full P2B87 diagnosis for your vehicle
Year, make, model + step-by-step repair help — free plan included.