For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
Schematic Reference: HVAC Schematics Connector End View Reference: Component Connector End Views
1 |

1. Turn the ignition to ON.
2. Observe the temperature indication screen of the controller.

Does the digit go ON and OFF?

--

Go to Step 2

Go to Step 3

2 | Perform the Diagnostic System Check - HVAC Systems Automatic. Does the display indicate any error codes? | -- | Go to Diagnostic Trouble Code (DTC) List - Vehicle | --
3 | Inspect fuse F7 in the instrument panel (I/P) fuse block. Is the fuse in good condition? | -- | Go to Step 5 | Go to Step 4
4 | Replace fuse F7. Did you complete the replacement? | -- | System OK | --
5 | Inspect fuse EF3 in the engine fuse block. Is this fuse in good condition? | -- | Go to Step 7 | Go to Step 6
6 | Replace fuse EF3. Did you complete the replacement? | -- | System OK | --
7 |

1. Turn the ignition switch to ON.
2. Measure the voltage between the ground and terminal 87 (Violet) of the blower relay.

Is the voltage measured within the specified range?

11-14 V

Go to Step 15

Go to Step 8

8 | Measure the voltage between the ground and terminal 86 (Brown) at the blower relay. Is the voltage measured within the specified range? | 11-14 V | Go to Step 10 | Go to Step 9
9 |

1. Turn the ignition switch to OFF.
2. Inspect the circuit (Brown) between terminal 86 of the blower relay to F7 in the I/P fuse block.
3. Repair any problem found in the wiring or terminals at the relay socket or connector C201.

Did you find and correct the condition?

--

System OK

--

10 | Measure the voltage between the ground and terminal 30 (Red) at the blower relay. Is the voltage measured within the specified range? | 11-14 V | Go to Step 12 | Go to Step 11
11 |

1. Turn the ignition switch to OFF.
2. Inspect the circuit (Red) between terminal 30 of the blower relay to EF3 in the engine fuse block.
3. Repair any problem found in the wiring or terminals at the fuse block connector C105, connector C202, or at the relay socket.

Did you find and correct the condition?

--

System OK

--

12 |

1. Turn the ignition switch to OFF.
2. Measure the continuity in the wiring harness between the blower relay terminal 85 (Black) and ground.

Does the ohmmeter show the specified value?

0 Ω

Go to Step 14

Go to Step 13

13 | Repair any condition found in terminal 85 at the relay connector, circuit (Black), connector C201, or ground G201. Did you complete the repair? | -- | System OK | --
14 | Replace the blower relay. Did you complete the replacement? | -- | System OK | --
15 |

1. Turn the ignition switch to OFF.
2. Disconnect the wiring harness at the blower motor.
3. Turn the ignition switch to ON.
4. Measure the voltage between the ground and blower connector 1 (Yellow).

Is the voltage measured within the specified range?

11-14 V

Go to Step 17

Go to Step 16

16 |

1. Turn the ignition switch to OFF.
2. Inspect the circuit (Yellow) between the blower connector terminal 1 and blower relay terminal 87.
3. Repair any problem found in the wiring or a connector terminal at the blower connector, connector C208, or the blower relay socket.

Did you find and correct the condition?

--

System OK

--

17 | Measure the resistance between the connector terminals on the blower motor. Does the resistance measured equal the specified value? | 5 Ω | Go to Step 19 | Go to Step 18
18 | Replace the blower motor. Did you complete the replacement? | -- | System OK | --
19 | Measure the resistance of the circuit (Violet) between terminal 2 of the blower connector and terminal 30 of the MAX HI relay and terminal 6 of the power transistor. Does the resistance measured equal the specified value? | 0 Ω | Go to Step 21 | Go to Step 20
20 | Repair the problem in the circuit (Violet). Did you complete the repair? | -- | System OK | --
21 | Measure the resistance of the circuit (Black) from terminal 3 of the power transistor connector to ground. Does the resistance measured equal the specified value? | 0 Ω | Go to Step 23 | Go to Step 22
22 |

1. Inspect the circuit (Black) from terminal 3 of the power transistor connector and terminal 87 of the Max HI relay to ground G203.
2. Repair any problem found in the wiring, ground G203.

Did you find and correct the condition?

--

System OK

--

23 | Replace the automatic temperature control (ATC) controller. Did you complete the replacement? | -- | System OK | --