For 1990-2009 cars

Table 1: | Reference Table

#### Reference Table

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

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

• | A faulty blower motor resistor. Test the blower motor resistor for an open. Refer to Circuit Testing in Wiring Systems and Blower Motor Resistor Replacement .

Blower motor inoperative in High speed only |

• | An open in the blower motor ground circuit between S200 and the blower switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

• | A faulty blower switch. Test the blower switch for an open. Refer to Circuit Testing in Wiring Systems and Blower Switch Replacement .

Blower motor operates at High speed only |

• | An open between S200 and the blower motor resistor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

• | A faulty blower switch. Test the blower switch for an open. Refer to Circuit Testing in Wiring Systems and Blower Switch Replacement .

• | A faulty blower motor resistor. Test the blower motor resistor for an open. Refer to Circuit Testing in Wiring Systems and Blower Motor Resistor Replacement .

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: HVAC Schematics DEFINITION: Blower motor inoperative in Medium 1 or Medium 2.
1 | Did you review the Air Delivery Description and Operation and the Air Temperature Description and Operation perform the necessary inspections? | Go to Step 2 | Go to Symptoms - HVAC Systems - Manual
2 | Operate the blower motor at each speed. Is the blower motor inoperative at one speed only? | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
3 | Test the affected blower speed circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 8 | Go to Step 4
4 | Test the blower motor resistor for an open in the affected speed. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did the blower motor resistor test OK? | Go to Step 6 | Go to Step 5
5 | Replace the blower motor resistor. Refer to Blower Motor Resistor Replacement . Did you complete the replacement? | Go to Step 8 | --
6 | 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 8 | Go to Step 7
7 | Replace the blower switch. Refer to Blower Switch Replacement . Did you complete the replacement? | Go to Step 8 | --
8 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3