Circuit Description
The Winter Mode shift program is available when certain conditions are met. Refer to Winter Mode Operation . Ignition voltage is supplied directly to the Winter Mode indicator bulb in the Winter Mode switch. The transmission control module (TCM) controls the lamp by grounding the control circuit with an internal driver. The Winter Mode Selector Switch signal circuit is pulled up to B+ within the TCM. The other side of the switch connects to ground. When the switch is on, the signal voltage is pulled low. The TCM toggles the Winter Mode with each press of the button. The Winter program selection causes the transmission to start in 3rd gear. The reduced torque in third gear decreases wheelspin in slippery conditions.
The Winter Mode switch has two states of illumination. When the ignition switch is on, the snowflake symbol dimly illuminates from an internal bulb. When Winter Mode is active, a second lamp causes the snowflake symbol to illuminate brightly.
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
-
If the switch illumination lamp is functioning, the feed circuit is OK.
-
If the switch illumination lamp is functioning, the feed circuit is OK.
Step | Action | Value(s) | Yes | No | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform Powertrain On Board Diagnostic (OBD) System Check - Automatic Transmission ? | -- | Go to Powertrain On Board Diagnostic (OBD) System Check - Automatic Transmission | |||||||||
2 | Any DTCs must be corrected before performing this diagnostic procedure. Are any DTCs set? | -- | Go to the applicable DTCs | |||||||||
3 |
Caution: Apply the parking brake and block the drive wheels before performing this procedure in order to prevent bodily injury. Does the Winter Mode indicator lamp turn ON and OFF? | -- | Go to Intermittent Conditions in Engine Controls | |||||||||
4 |
Does the display change back and forth between ON and OFF? | -- | ||||||||||
5 | Command the Winter Mode indicator lamp ON and OFF with the Scan Tool . Does the lamp turn ON and OFF? | -- | ||||||||||
Is the lamp always ON? | -- | |||||||||||
Is the switch illumination lamp ON? | -- | |||||||||||
8 |
Caution: When you are performing service on or near the SIR components or the SIR wiring, you must disable the SIR system. Refer to Disabling the SIR System. Failure to follow the correct procedure could cause air bag deployment, personal injury, or unnecessary SIR system repairs. Does the Winter Mode indicator lamp illuminate? | -- | ||||||||||
9 | Test the Winter Mode Indicator Lamp circuit for the following conditions:
Did you find and correct a condition? | -- | -- | |||||||||
10 |
Caution: When you are performing service on or near the SIR components or the SIR wiring, you must disable the SIR system. Refer to Disabling the SIR System. Failure to follow the correct procedure could cause air bag deployment, personal injury, or unnecessary SIR system repairs. Does the lamp illuminate? | -- | ||||||||||
11 | Does the display always indicate ON? | -- | ||||||||||
12 |
Caution: When you are performing service on or near the SIR components or the SIR wiring, you must disable the SIR system. Refer to Disabling the SIR System. Failure to follow the correct procedure could cause air bag deployment, personal injury, or unnecessary SIR system repairs. Does the scan tool display change each time the jumper is momentarily connected? | -- | ||||||||||
13 |
Did you detect continuity? | -- | ||||||||||
14 |
Caution: When you are performing service on or near the SIR components or the SIR wiring, you must disable the SIR system. Refer to Disabling the SIR System. Failure to follow the correct procedure could cause air bag deployment, personal injury, or unnecessary SIR system repairs. Connect the Winter Mode selector switch signal circuit (terminal A of the switch harness connector) to ground with a fused jumper wire while observing the Scan Tool . Does the display indicate ON? | -- | ||||||||||
15 |
Is the resistance within the specified range? | 0-5 ohms | ||||||||||
16 | Repair the short to ground in the lamp control circuit. Is the action complete? | -- | -- | |||||||||
17 | Repair the feed circuit to the Winter Mode Switch indicator lamps. Is the action complete? | -- | -- | |||||||||
18 | Repair the signal circuit shorted to ground. Is the action complete? | -- | -- | |||||||||
19 | Repair the open/high resistance signal circuit. Is the action complete? | -- | -- | |||||||||
20 | Test the ground circuit to the Winter Mode switch for the following conditions:
Did you find and correct the condition? | -- | ||||||||||
21 | Replace the Winter Mode switch. Is the action complete? | -- | -- | |||||||||
22 | Inspect the TCM harness connector for a poor connection or poor terminal tension. Refer to General Electrical Diagnosis in Wiring Systems. Did you find and correct the condition? | -- | ||||||||||
23 |
Caution: When you are performing service on or near the SIR components or the SIR wiring, you must disable the SIR system. Refer to Disabling the SIR System. Failure to follow the correct procedure could cause air bag deployment, personal injury, or unnecessary SIR system repairs. Replace the TCM. Refer to Transmission Control Module Replacement . Is the action complete? | -- | -- | |||||||||
24 |
Caution: Apply the parking brake and block the drive wheels before performing this procedure in order to prevent bodily injury. Does the Winter Mode indicator lamp turn ON and OFF? | -- | System OK |
