What Does B2468 Mean?
This code indicates the Body Control Module (BCM) has detected a short to ground in the auxiliary heater coolant pump control circuit. The auxiliary heater system, commonly found in diesel vehicles or cold-climate vehicles, uses an electric pump to circulate coolant through a supplemental heating element. The BCM detected abnormally low resistance or voltage in the pump control circuit, indicating current is flowing directly to ground rather than through the intended load.
Common Causes
45%
Damaged or chafed wiring harness causing short to ground between BCM and coolant pump
30%
Failed auxiliary heater coolant pump with internal short to ground
15%
Corroded or water-damaged connector at pump or BCM causing ground fault
10%
Failed BCM output driver circuit for pump control
Diagnostic Steps
1
Step 1: Perform visual inspection of auxiliary heater coolant pump and associated wiring harness for obvious damage, chafing, burned wires, or corroded connectors. Pay special attention to areas where harness passes near sharp edges or heat sources.
2
Step 2: Disconnect auxiliary heater coolant pump electrical connector. Using a digital multimeter, measure resistance between pump power terminal and pump ground/case. Resistance should be within manufacturer specification (typically 2-8 ohms). Zero or near-zero resistance indicates internal pump short.
3
Step 3: With pump disconnected, measure resistance between BCM control wire terminal (vehicle harness side) and known good chassis ground. Reading should be infinite (open circuit). Low resistance indicates wiring harness short to ground.
4
Step 4: Inspect connector terminals and pump mounting area for moisture intrusion, corrosion, or damaged seals. Check pump mounting bracket for sharp edges that may have damaged wire insulation.
5
Step 5: If wiring and pump test good, perform voltage drop test on ground circuit while commanding pump activation through scan tool active test function. Excessive voltage drop indicates poor ground connection.
6
Step 6: After repairs, clear codes and perform active test of auxiliary heater pump through scan tool to verify proper operation and confirm no short to ground condition remains. Monitor live data for appropriate current draw.
Estimated Repair Cost
$150 - $650
Parts + labor, varies by vehicle and location
This code indicates the Body Control Module (BCM) has detected a short to ground in the auxiliary heater coolant pump control circuit. The auxiliary heater system, commonly found in diesel vehicles or cold-climate vehicles, uses an electric pump to circulate coolant through a supplemental heating el...
The most common cause of B2468 (Aux Heater Coolant Pump Circuit Short to Ground) is: Damaged or chafed wiring harness causing short to ground between BCM and coolant pump
Typical repair costs for B2468 range from $150 to $650, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Safe to continue driving as this affects supplemental heating only and does not impact primary engine cooling or safety systems. Repair at convenience, though cold weather comfort will be reduced and engine warm-up time may be longer in diesel applications.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B2468 to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Body
System
Auxiliary Heating System
Difficulty
Type
Generic (SAE)
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
