P269C: Exhaust Aftertreatment Glow Plug Control Performance

P269C is the plausibility counterpart to the electrical control codes: the wires test fine, yet the control stage of the exhaust glow plug does not behave as commanded, for example a relay or driver that does not report the expected state or reacts too slowly. No manufacturer documents this code publicly. The closest documented case is Ford's 3.2 L Transit, where a vaporizer glow plug relay whose feedback disagrees with the command for about 60 s is a recorded fault, filed under P26A0 from 2017 and under P2689 before. CARB requires functional checks of such output components wherever feasible, beyond pure circuit continuity. An affected engine would lose or limit exhaust fuel vaporization, so regeneration suffers and the MIL can be expected.

Low severity. Can I keep driving?You can keep driving, although cold starts will be harder. Avoid cranking the starter repeatedly on cold days.

Symptoms

MIL on
Particulate filter regeneration incomplete

Most likely causes

Glow plug relay switching late or not at all
Faulty feedback signal from the relay or driver
Low system voltage during the control check

What to check, in order

Start with the simplest. You can tick off each step.

Check the fuse and connector
Compare the reading with other engine data while varying the engine speed.
Measure the resistance of each glow plug with the engine cold
Check the power supply during the preheat cycle
Test the module or relay if the glow plugs are good

Good to know

Repair difficulty: medium
It affects emissions.

What each character of P269C means

P: Powertrain: engine and transmission
2: Generic code: same on every make
6: Control modules and outputs
9C: Specific fault in that system

Frequently asked questions

Can I keep driving with code P269C?

You can keep driving, although cold starts will be harder. Avoid cranking the starter repeatedly on cold days.

What causes code P269C?

The most common causes are: glow plug relay switching late or not at all; faulty feedback signal from the relay or driver; low system voltage during the control check.

Related codes

Sources

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.