Powertrain, generic (extended)

P215F Reductant Heater D Current Too High

Check engine lightOn

EmissionsRelevant

Drive cycleRequired

Limp modePossible

P215F is set when heater D of the DEF system pulls more current than its design allows, which points to a partly shorted element or a leak path to ground in its wiring. The letter D is assigned by each maker, and many systems have only three heaters. No maker documents P215F publicly. As a guide, GM's 2025 Duramax tables trip the high-current codes of heaters A to C above 15 A in 40 samples of 0.1 s and treat them as Type A, and Ford's 2023 diesel summary detects an overloaded tank or line heater within 2.2 s. The controller usually switches the faulty element off to protect its driver, so the fluid in that area is no longer heated. Wet connectors, chafed leads and internal shorts are typical. The low-current partner is P215E; circuit faults are P20C5 to P20C8.

Likely causes

Heating element D partly shorted internally

Moisture or DEF crystals in the heater D connector bridging pins

Chafed heater lead touching ground or a neighbouring circuit

Symptoms

Check engine light with a DEF or emission system warning
DEF stays frozen in the affected area during cold weather
Blown heater fuse in some cases

Repair estimate

DifficultyMediumWorkshop job

Parts and labour€80–900

Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

reductant line heater d

References: law.cornell.edu, gsi.ext.gm.com, fordservicecontent.com.