Circuit Description
The passenger temperature control is a sliding potentiometer with detents that correspond to fixed resistance values. The heater and A/C programmer determines which switch position has been selected by the voltage drop across the corresponding resistance value.
Conditions for Running the DTC
The ignition is turned ON.
Conditions for Setting the DTC
The heater and A/C programmer detects that the signal circuit of the passenger temperature control is less than 0.09 V (5 counts) or greater than 4.90 V (250 counts).
Action Taken When the DTC Sets
The heater and A/C programmer will ignore the passenger temperature control. The data displayed on the scan tool, 3.19 V (163 counts) in the HVAC System Data list, will be the default value.
Conditions for Clearing the DTC
| • | The DTC will become history if the heater and A/C programmer no longer detects a failure. |
| • | The history DTC will clear after 50 fault free ignition cycles. |
| • | The DTC can be cleared with a scan tool. |
Diagnostic Aids
Switch Position | Counts | Volts |
|---|---|---|
COOL | 67 | 1.31 |
COOL | 106 | 2.10 |
COOL | 132 | 2.60 |
COOL | 150 | 2.96 |
NEUTRAL | 163 | 3.19 |
WARM | 174 | 3.41 |
WARM | 182 | 3.57 |
WARM | 189 | 3.70 |
WARM | 194 | 3.80 |
Refer to Testing for Intermittent Conditions and Poor Connections .
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the HVAC Diagnostic System Check? | -- | Go to Step 2 | Go to Diagnostic System Check |
2 |
Does the scan tool indicate that the Pass HVAC Control parameter changes state? | -- | Go to Diagnostic Aids | Go to Step 3 |
3 |
Does the voltage measure near the specified value? | 5 V | Go to Step 4 | Go to Step 5 |
4 | Measure the voltage from the signal circuit of the passenger temperature control to the ground circuit of the passenger temperature control. Does the voltage measure near the specified value? | 5 V | Go to Step 7 | Go to Step 6 |
5 | Test the signal circuit of the passenger temperature control for a short to ground, a short to voltage, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 8 |
6 | Test the ground circuit of the passenger temperature control for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 8 |
7 | Inspect for poor connections at the harness connector of the passenger temperature control. 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 11 | Go to Step 9 |
8 | Inspect for poor connections at the harness connector of the heater and A/C programmer. 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 11 | Go to Step 10 |
9 | Replace the passenger temperature control. Refer to Control Assembly Replacement - Passenger . Did you complete the replacement? | -- | Go to Step 11 | -- |
10 | Replace the heater and A/C programmer. Refer to Programmer Replacement . Did you complete the replacement? | -- | Go to Step 11 | -- |
11 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
