For 1990-2009 cars

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
1 | Allow the engine to cool to room temperature. With the ignition ON, does the temperature gage always read at the high end of the scale? | -- | Go to Step 7 | Go to Step 2
2 | Disconnect engine control module (ECM) electrical connector. Does the temperature gage indicator drop to the low end of the scale? | -- |

• | DTC P0117 or P0118 for the 1.2L engine

• | DTC P0117 or P0118 for the 1.4L DOHC engine

• | DTC P0117 or P0118 for the 1.4L SOHC engine

• | DTC P0117 or P0118 for the 1.5L engine

• | DTC P0117 or P0118 for the 1.6L (L91) engine

Go to Step 3

3 | Inspect for a short to ground between the ECM and the temperature gage. Is there a short to ground? | -- | Go to Step 4 | Go to Step 5
4 | Repair the short to ground. Is the repair complete? | -- | System OK | --
5 | Replace the temperature gage. Is the repair complete? | -- | System OK | --
6 |

1. Disconnect the ECM.
2. Turn the ignition ON.
3. Check the voltage at the ECM.

Does the voltage equal the value specified?

11-14 V

Go to Step 9

Go to Step 7

7 | Inspect for an open circuit between the ECM and the temperature gage. Is there an open circuit? | -- | Go to Step 8 | Go to Step 5
8 | Repair the open circuit between the ECM and the temperature gage. Is the repair complete? | -- | System OK | --
9 |

1. Disconnect the ECM.
2. Connect a jumper wire between the ECM connector and ground.
3. Turn the ignition ON.

Does the temperature gage move to the high end of the scale?

--

• | DTC P0117 or P0118 for the 1.2L engine

• | DTC P0117 or P0118 for the 1.4L DOHC engine

• | DTC P0117 or P0118 for the 1.4L SOHC engine

• | DTC P0117 or P0118 for the 1.5L engine

• | DTC P0117 or P0118 for the 1.6L (L91) engine

Go to Step 5