For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Was the entire HVAC System Check performed? | -- | Go to Step 2 | Go to HVAC System Check
2 |

1. Place the ignition switch in the RUN position.
2. With a test light, backprobe the heater-A/C control between connector C1 terminal B and ground.

Is the test light on?

--

Go to Step 3

Go to Step 4

3 |

1. Place the heater-A/C control in position 1.
2. With a test light, backprobe the heater-A/C control between connector C1 terminal H and ground.

Is the test light on?

--

Go to Step 5

Go to Step 6

4 | Is the FRT HVAC LOW/MED BLWR Fuse open? | -- | Go to Step 12 | Go to Step 13
5 | Connect a test light between the blower motor connector terminal A and terminal B. Is the test light on? | -- | Go to Step 7 | Go to Step 8
6 | Replace the heater-A/C control. Refer to Control Assembly Replacement . Is the repair complete? | -- | Go to Step 11 | --
7 | Replace the blower motor. Go to Blower Motor and Fan Replacement . Is the repair complete? | -- | Go to Step 11 | --
8 | Connect the test light between the blower motor resistor connector terminal E and B+. Is test light on? | -- | Go to Step 9 | Go to Step 10
9 | Replace the blower motor resistor. Refer to Blower Motor Resistor Replacement . Is the repair complete? | -- | Go to Step 11 | --
10 | Repair the poor connection or open in CKT 150. Is the repair complete? | -- | Go to Step 11 | --
11 |

1. Turn the ignition switch to the OFF position.
2. Reconnect all connectors/components removed.

Have all the repairs been made?

--

Go to HVAC System Check

--

12 |

1. Turn the igntion switch to the OFF position.
2. Disconnect the heater-A/C control connector C1.
3. Check for a short to ground in CKT 41.

Is a short to ground present?

--

Go to Step 14

Go to Step 6

13 | Repair the open in CKT 41 between heater-A/C control and the fuse block. Is the repair complete? | -- | Go to Step 11 | --
14 | Repair a short to ground in CKT 41. Is the repair complete? | -- | Go to Step 11 | --