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DTC codes / Chrysler codes / P1250

P1250 · ChryslerEarly Fuel Evaporation Heater Circuit

P1250 on Chrysler vehicles indicates that the powertrain control module has detected a fault in the early fuel evaporation heater circuit, which is the electrical path that powers the heater grid used to warm intake air or fuel during cold starts. The computer monitors the circuit for expected voltage and current behavior and sets this code when the signal falls outside the programmed range.

SystemPowertrain
Code typeChrysler specific
SeverityLow
Fix difficultyIntermediate
AreaFuel and air metering (injector circuits)

Symptoms you may notice

  • Illuminated check engine light, often with no other symptoms
  • Rough idle or stumble during cold starts in low ambient temperatures
  • Slightly higher fuel consumption during warm-up
  • Hesitation or flat spot when accelerating from a cold start
  • In rare cases, a noticeable fuel odor or evaporative emissions smell

Common causes, most likely first

  1. Failed early fuel evaporation heater element (open or shorted grid)
  2. Damaged or corroded wiring harness connector at the heater
  3. Blown fuse or fusible link supplying the heater circuit
  4. Open or shorted power or ground wire between the PCM and heater
  5. Faulty powertrain control module driver for the heater circuit
  6. Corrosion or water intrusion in the heater connector causing high resistance

How to diagnose and fix it

  1. Check the fuse and fusible link for the early fuel evaporation heater circuit first
  2. Inspect the heater connector and wiring for corrosion, chafing, or loose pins
  3. Measure resistance across the heater element and compare to specification
  4. Backprobe the heater circuit at the PCM to verify power and ground signals
  5. Test the PCM driver output with a test light or oscilloscope if the circuit is intact
  6. Replace the faulty heater element or repair the wiring as needed
  7. Clear the code and verify the repair with a cold-start drive cycle

What most technicians overlook on P1250

  • A heater grid that tests good cold can still fail when hot, so resistance checks should be repeated after the engine reaches operating temperature.
  • Corroded connector pins at the heater are a frequent cause on older Chrysler vehicles, and the corrosion often hides behind the rubber boot.
  • The PCM driver can be damaged by a shorted heater element, so always check the element before replacing the computer.
  • P1250 can set intermittently due to a loose ground connection at the engine block, which is easy to miss when testing only the heater circuit.
  • Some Chrysler models use a relay in the heater circuit, and a failing relay can mimic a bad heater element.

Can I keep driving with P1250?

The vehicle is safe to drive with P1250 because the fault mainly affects cold-start emissions and warm-up performance, but avoid extended idling in cold weather and have the circuit inspected soon to prevent potential PCM damage.

Tools that help

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Guidance is general and written for Chrysler vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

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