What Does B2469 Mean?
This code indicates the Body Control Module (BCM) or heating system control module detected an open circuit in the auxiliary heater coolant pump control circuit. The auxiliary heater system, commonly found in diesel vehicles or cold-climate vehicles, uses an electric coolant pump to circulate coolant through a supplemental heating element. An open circuit means there is a break in the electrical path preventing current flow to the pump, which could be due to wiring damage, connector issues, or pump motor failure.
Common Causes
45%
Damaged wiring or corroded connectors in the auxiliary heater coolant pump circuit
30%
Failed auxiliary heater coolant pump motor with open windings
15%
Blown fuse or faulty relay in the auxiliary heater pump power supply circuit
10%
Failed control module (BCM or auxiliary heater control unit) unable to command pump
Diagnostic Steps
1
Step 1: Locate the auxiliary heater coolant pump (typically near firewall or under vehicle) and perform visual inspection of pump, wiring harness, and electrical connector for physical damage, corrosion, loose pins, or burnt terminals
2
Step 2: Check fuse and relay for auxiliary heater system in fuse box using continuity test; replace if blown and retest circuit for immediate repeat failure indicating short circuit
3
Step 3: Disconnect pump connector and measure resistance across pump motor terminals using multimeter; should read 1-5 ohms typically (consult vehicle specs); infinite resistance indicates open motor windings requiring pump replacement
4
Step 4: With pump disconnected, measure voltage at pump connector harness side while commanding pump activation via scan tool active test; should see battery voltage (12-14V); no voltage indicates wiring or control module issue
5
Step 5: If no voltage present at pump connector, backprobe control module connector pins for pump circuit and check for continuity to pump connector and to ground; repair open circuit in wiring as needed
6
Step 6: After repairs, clear codes, perform active test of auxiliary heater pump function via scan tool, and monitor for proper operation and absence of code return during test drive with heater activated
Estimated Repair Cost
$150 - $600
Parts + labor, varies by vehicle and location
This code indicates the Body Control Module (BCM) or heating system control module detected an open circuit in the auxiliary heater coolant pump control circuit. The auxiliary heater system, commonly found in diesel vehicles or cold-climate vehicles, uses an electric coolant pump to circulate coolan...
The most common cause of B2469 (Aux Heater Coolant Pump Circuit Open) is: Damaged wiring or corroded connectors in the auxiliary heater coolant pump circuit
Typical repair costs for B2469 range from $150 to $600, depending on the vehicle, location, and whether you do it yourself or go to a shop.
This is safe to drive as it only affects supplemental cabin heating performance and does not impact primary engine cooling or vehicle operation. Repair at convenience, though cabin heating effectiveness will be reduced in cold weather conditions.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B2469 to identify the root cause.
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Quick Info
Category
Body
System
Auxiliary Heating System
Difficulty
Type
Generic (SAE)
Recommended Tools
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