A customer drove his Chevrolet Cruze to my garage,and told the check engine light on.He asked to find the reason and repair it.Here I share this real case on how to repair Chevrolet Cruze check engine light on thoroughly.Hope this article would give some useful info when you dealing with simlar check engine light trouble.
Inspection and analysis:
Technicians found the trouble code:P0113–Intake Air Temperature Circuit High Input.
After consulting,trouble code P0113 is caused by condition of intake air temperature lower than -60℃ and it keeps over 4s.
Checked the stream data and found that the intake air temperature was 26℃,it was normal.Shaked the wire harness,the data did not change.The intake air temperature sensor is integrated on the air flow meter.Inspect the connector of air flow meter,no abnormality found.
The wire harness of air flow meter locate on the air filter shell and engine.The vibration generated by engine runing will transmit to he harness,which may damage the wire harness.So coat the anti-oxidation grease on each connector of air flow meter to avoid poor connecting.
Technicians asked the customer to drive his Chevrolet Cruze back and for several days driving test.But 2 days later,the customer drove it back and the check engine light on again.This technicians found the trouble code P0101–Mass Air Flow Sensor Performance Trouble.It caused by the air mass flow go beyond the limit over 1s.Check the frozen frame data,it showed the air flow was 0g/s when the trobule occuring.It may caused by open circuit.Then technicians checked the current data,but it was normal.
Shake the engine wire harness and ECU connector,and data showed normally.Because the connector of air flow meter had been dealed,so technician detemined it work normally.Technicians dealed with the ECU with the anti-anti-oxidation grease treatment and repalced a new air flow meterl.So even it can not solve this trouble thoroughly,but it would narrow the scope of the trouble causes.
Ask customer to drive for several day testing,but just 3 day later,he came back with the check engine light on.This time technician found the trobule code P0114–Intake Air Temperature Circuit Intermittent.The generated condition of P0114 is intake temperature rangeability greater than 10℃ within 0.1s and it keeps over 2s.
Up to now,technicians have replaced air flow meter and dealed the connector of ECU,so it most likely the wire harness fault.Checked the intake temperature when shaking the engine wire harness,but the data did not change.And inspected the wire harness,there was not any damage on it.Technicians had to replace the air flow meter forpossibility of new parts performance anomalies,but it not sure to solve this problem.
Inevitably,the customer came back fourth time.And trouble code P0101–Mass Air Flow Sensor Performance Trouble and P0102–Mass Air Flow (MAF) Circuit Low were read out.Checked the frozen frame data,the air flow was 0g/s when these two troule code generating.
Checked the air flow data and sharked the connector of air flow meter,but the data didn’t change.Then checked the data diagram when sharking wire harness by data playback function of diagnostic tool.Technicians found the data transition phenomenon(show below).Checked the data diagram when shaking the wire connector of air flow meter in different direction,and found the data will change obviously when shaking in a certain direction.
Disconnect the connector terminal of air flow meter,and found the spring tabs of num 2 terminal was damaged.
Check the circuit diagram as below,the damaged terminal are the intake air temperature sensor signal line and air flow meter signal line.The probability of the two terminals was damaged was very low.And this coincidence result in the trouble difficuly to solve and occur again and again with diffenent trouble code.Because the damaged terminals are very small,it is difficult to fix,so it must to repalce new wire harness.
Replace engine wire harness,the trouble was solved thoroughly.