Reductant Heater Performance
The reductant heating element is not operating properly.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The vehicle's system heats the fluid used for emissions control, and it's not heating up like it should, which can cause increased exhaust emissions.
What the computer is actually seeing
The engine control module (ECM) monitors the amperage and temperature of the reductant heater. If the heater stays below the required temperature for a set duration (usually more than 10 seconds) or draws incorrect amperage, it triggers this code.
What a healthy reading looks like
Heater resistance should be around 1-5 ohms when cold. The voltage at the heater connector should be near battery voltage (12-14V) when activated.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Inspect the reductant heater wiring and connectors for damage or corrosion. - If damaged, repair or replace as needed. - If no issues, proceed to step 2.
- 22. Check the fuse for the reductant heater circuit. - If blown, replace and retest. - If OK, proceed to step 3.
- 33. With the engine running, measure voltage at the heater connector. It should be approximately 12-14V. - If there's no voltage, check for wiring issues back to the ECM. - If voltage is present, proceed to step 4.
- 44. Measure the resistance of the reductant heater itself with a multimeter. - If resistance is out of expected range (1-5 ohms), the heater is likely faulty and should be replaced. - If resistance is normal, further diagnose potential ECM issues.
Common causes
- Failed reductant heater
- Faulty wiring or connections to the heater
- ECM failure
- Blown fuse for the reductant heater circuit
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's drivable, but you may experience increased emissions and potential issues with the diesel exhaust fluid system.
Will this code come back after clearing?
If the underlying issue is not resolved, the code will return after a drive cycle.
Why does this pair with other codes?
This is often related to the overall function of the reductant system, which includes heaters and sensors.
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