P0B38

Motor Electronics Coolant Pump B Control Circuit/Open

Severity

🔴 High

Can you drive?

Do not drive — repair immediately

Approx. repair cost

$167–444 (est.)

Symptoms

Electronics overheat warning on instrument panel
Reduced engine power (in hybrid systems)
Activation of emergency operation
Noise or hum from the cooling pump
Overheating of electronic components

Causes

Broken or damaged control circuit wiring
Pump motor malfunction
Problems with the pump circuit relay or fuse
Corrosion of contacts in connectors
Mechanical failure of the pump (jamming)

How to Fix

Check the pump circuit fuses and relays
Testing the resistance of pump motor windings
Check the integrity of wiring and connectors
Diagnostics of control signals from the computer
Replacing a faulty cooling pump

Related codes

P0B39 P0B3A P0B37