Exhaust Aftertreatment Glow Plug Control Circuit/Open
The P269B code indicates a fault in the control circuit of the exhaust aftertreatment glow plug, which is used to heat the diesel particulate filter (DPF) during regeneration. The powertrain control module (PCM) has detected an open circuit or a malfunction in the glow plug control circuit, preventing proper heating and regeneration of the DPF. This can lead to increased emissions and potential clogging of the exhaust system.
1. Most Common Causes
- Open or short circuit in the glow plug wiring harness
- Faulty exhaust aftertreatment glow plug
- Failed glow plug control module or relay
- Corroded or damaged electrical connectors
2. Symptoms You Will Notice
- Illuminated check engine light
- Reduced engine performance or power
- Increased exhaust emissions
- Frequent DPF regeneration cycles or clogging
3. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for related codes.
Step 2: Visually inspect the glow plug wiring and connectors for damage, corrosion, or loose connections.
Step 3: Measure resistance of the glow plug; compare to manufacturer specifications.
Step 4: Test the control circuit voltage and ground at the glow plug connector with the ignition on.
Step 5: If wiring and plug are okay, test the glow plug control module/relay for proper operation.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as the DPF may clog, leading to costly repairs. Short trips may be possible but should be limited.
How much does it cost to fix?▼
Repair costs typically range from $150 to $400, depending on the cause and labor rates. Replacing a glow plug is usually $100-$200, while control module replacement can be $200-$400.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.