P269B — Exhaust Aftertreatment Glow Plug Control Circuit/Open
OBD2 code P269B flags a problem with the diesel glow plug system (exhaust aftertreatment glow plug control circuit/open). The car is usually drivable while you plan the repair. Common culprits: faulty glow plug relay or control module, corroded glow plug connectors, burned-out glow plug.
powertrain (engine/transmission)
Is it safe to drive?
Short-term driving is OK Safe to drive once the engine is started and warmed up. The main risk is cold-weather starting: with several dead plugs the engine may not start on a cold morning. Fix before winter.
How to diagnose with an OBD scanner
- Read the code and freeze frame Connect an OBD2 scanner, confirm P269B is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
- Check for companion codes and TSBs Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
- Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the diesel glow plug system for damage, corrosion, chafing or poor contact.
- Subsystem check Measure resistance of each glow plug — an open plug reads infinite resistance.
- Subsystem check Check voltage at the glow plug rail during the pre-glow phase.
- Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P269B does not return.
Approximate repair cost
Repair cost depends on which component actually failed. Typical scenarios for P269B (parts and labor, USD, independent shop rates): Replace one glow plug: $80–$200; Replace a full set of glow plugs: $250–$600; Replace the glow plug relay/module: $150–$450. Overall, fixing P269B usually costs between $80 and $600. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.
Common questions
Will P269B clear itself?
Sometimes P269B clears after a few drive cycles if the fault was intermittent — for example a loose connector or a tank of bad fuel. The underlying cause usually remains, so the code tends to return. Clear it once; if it comes back, diagnose rather than erase it repeatedly.
How much does it cost to fix P269B?
Replace one glow plug — $80–$200; Replace a full set of glow plugs — $250–$600; Replace the glow plug relay/module — $150–$450. Exact cost depends on the root cause, your vehicle and local labor rates — a proper diagnosis is the cheapest first step.
How do I diagnose P269B myself?
Start with a scan: confirm P269B, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the diesel glow plug system, and verify the suspect component against live data before buying parts.
What are the symptoms of P269B?
Drivers most often notice: rough idle until warmed up, hard starting in cold weather, white smoke after a cold start, Check Engine Light on.
Is it safe to drive with P269B?
Safe to drive once the engine is started and warmed up. The main risk is cold-weather starting: with several dead plugs the engine may not start on a cold morning. Fix before winter.
What does P269B mean?
The engine control module sets P269B when it detects a fault in the diesel glow plug system. In practical terms: exhaust aftertreatment glow plug control circuit/open. The code belongs to the powertrain (engine/transmission) group of OBD2 codes.
This code does not appear from a single bad reading: the module must see the fault condition repeat under defined operating conditions before it turns on the warning light. The freeze frame captured with P269B — engine load, rpm, temperature, speed — tells you exactly when the problem occurs, so reproduce those conditions when testing.
Common symptoms of P269B
- rough idle until warmed up
- hard starting in cold weather
- white smoke after a cold start
- Check Engine Light on
- glow plug warning light staying on
What causes P269B?
- corroded glow plug connectors
- blown fuse in the glow plug circuit
- burned-out glow plug
- faulty glow plug relay or control module
- damaged glow plug wiring or connector
How to diagnose P269B
- Connect an OBD2 scanner, confirm P269B is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
- Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
- Visually inspect the wiring harness and connectors related to the diesel glow plug system for damage, corrosion, chafing or poor contact.
- Measure resistance of each glow plug — an open plug reads infinite resistance.
- Check voltage at the glow plug rail during the pre-glow phase.
- Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P269B does not return.
How to fix P269B
Start with the cheapest and most common causes before replacing expensive parts:
- Replace one glow plug — $80–$200
- Replace a full set of glow plugs — $250–$600
- Replace the glow plug relay/module — $150–$450
How much does it cost to fix P269B?
Repair cost depends on which component actually failed. Typical scenarios for P269B (parts and labor, USD, independent shop rates):
- Replace one glow plug: $80–$200
- Replace a full set of glow plugs: $250–$600
- Replace the glow plug relay/module: $150–$450
Overall, fixing P269B usually costs between $80 and $600. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.
Can you drive with P269B?
Safe to drive once the engine is started and warmed up. The main risk is cold-weather starting: with several dead plugs the engine may not start on a cold morning. Fix before winter.