For 1990-2009 cars

Table 1: | Reference Table

#### Reference Table

Symptom | Causes
--- | ---
Blower motor inoperative in High speed only |

• | An open in the blower motor high speed circuit between S204 and the blower switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

• | An open blower switch. Refer to Circuit Testing in Wiring Systems and Blower Switch Replacement .

Blower motor operates at High speed only |

• | An open between S204 and the blower motor resistor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

• | An open blower switch. Refer to Circuit Testing in Wiring Systems and Blower Switch Replacement .

• | An open blower motor resistor. Refer to Circuit Testing in Wiring Systems and Blower Motor Resistor Replacement .

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: HVAC Schematics DEFINITION: Blower motor is inoperative in Low, Medium 1 or Medium 2.
1 | Did you review the Air Delivery Description and Operation and Air Temperature Description and Operation and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - HVAC Systems - Manual
2 | Operate the blower motor at each speed. Does the blower motor operate at all speeds? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3
3 |

1. Disconnect the blower motor resistor.
2. Test the blower motor resistor for an open in the affected speed. Refer to Circuit Testing in Wiring Systems and Blower Motor Resistor Replacement .

Did you find and correct the condition?

Go to Step 7

Go to Step 4

4 | Test the blower speed signal circuit of the affected speed for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 7 | Go to Step 5
5 | Inspect for a poor connection at the harness connector of the blower switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 7 | Go to Step 6
6 | Replace the blower switch. Refer to Blower Switch Replacement . Did you complete the replacement? | Go to Step 7 | --
7 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3