P01AC

Symptoms

• Inability to start on alternative fuel
• Automatic switching to main fuel
• Check Engine Light Illuminates
• Increased fuel consumption
• Unstable cold start

Causes

• Sensor wire short circuit to ground
• Temperature sensor circuit open
• Faulty tank temperature sensor
• Oxidation or damage to the sensor connector
• ECU malfunction (rare)

How to Fix

1. Read error codes and record data in case of failure
2. Check the voltage at the sensor connector (normal 4.5–5 V)
3. Check the wiring harness for breaks and short circuits
4. Measure the sensor resistance and compare with the norm
5. Clean the sensor connector from oxidation
6. If necessary, replace the alternative fuel tank temperature sensor

Related codes

Error P01AC by Vehicle Brand