OBD Guide

P01F8

Engine Coolant Heater A Control Circuit Driver Current/Temperature Too High

P01F8 is an OBD-II diagnostic trouble code meaning: Engine Coolant Heater A Control Circuit Driver Current/Temperature Too High. Common causes: short circuit in the heater circuit, control driver failure. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • Check Engine Light
  • Reduced preheating efficiency
  • Problems starting in cold weather
  • Heater overheating

Causes

  • Short circuit in the heater circuit
  • Control driver failure
  • Heater overheating
  • Wiring Harness Problems
  • Engine control unit malfunction

How to Fix

  1. Diagnostics of the heater control circuit
  2. Checking the resistance and insulation of the heater
  3. Inspect the wiring harness for damage
  4. Checking power and ground circuit
  5. Testing the control driver
  6. Replacing faulty components
  7. Resetting the error and checking the system operation

Related codes

Error P01F8 by Vehicle Brand

FAQ

What does the P01F8 code mean?

P01F8 is an OBD-II diagnostic trouble code that indicates: Engine Coolant Heater A Control Circuit Driver Current/Temperature Too High

What causes a P01F8 error code?

The most common causes of P01F8 include: Short circuit in the heater circuit; Control driver failure; Heater overheating; Wiring Harness Problems.

How do I fix a P01F8 diagnostic trouble code?

To fix P01F8: Diagnostics of the heater control circuit. Checking the resistance and insulation of the heater. Inspect the wiring harness for damage. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P01F8?

Limited driving only, diagnose soon

How much does it cost to fix P01F8?

The estimated repair cost for P01F8 is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat