Heated Steering Wheel Malfunction
Diagnostic Instructions
Diagnostic Fault Information
Circuit
|
Short to Ground
|
Open/High Resistance
|
Short to Voltage
|
Signal Performance
|
Ignition
|
1
|
1
|
-
|
-
|
Switch Signal
|
2
|
1
|
-
|
-
|
LED Control
|
4
|
4
|
5
|
-
|
Switch and LED Ground
|
-
|
1
|
-
|
-
|
Temperature Sensor Signal
|
3
|
3
|
3
|
-
|
Temperature Sensor Ground
|
-
|
3
|
-
|
-
|
Heater Element Control
|
3
|
3
|
2
|
-
|
Heater Element Ground
|
-
|
3
|
-
|
-
|
Module Ground
|
-
|
1
|
-
|
-
|
1. Heated Steering Wheel System Inoperative
2. Heated Steering Wheel Always ON
3. Heated Steering Wheel Inoperative
4. LED Inoperative
5. LED Always ON
|
|
| |
Circuit/System Description
The heated steering wheel control module controls the heated
steering wheel and the heated steering wheel ON indicator based on
an input from the heated steering wheel switch. When the heated
steering wheel switch is pressed, the switch signal circuit is
pulled to ground. This indicates to the heating steering wheel
control module that steering wheel heat is requested. When the
request is seen, the heated steering wheel control module supplies
voltage to the indicator lamp and supplies voltage to the heating
elements, which are internal to the steering wheel.
Reference Information
Schematic Reference
Steering Wheel Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Steering Wheel and Column Description and Operation
Electrical Information Reference
Circuit/System Verification
Ignition ON, press and release the heated steering wheel switch.
The heated steering wheel indicator should illuminate and the left
and right sides of the steering wheel should become warm.
If the heated steering wheel indicator does not illuminate, perform
the Switch and Controller Test. If the heated steering wheel
indicator illuminates but the steering wheel does not get warm,
perform the Heater and Controller Test.
Circuit/System Testing
Switch and Controller Test
| 1. |
Ignition OFF, disconnect the
harness connector at the heated steering wheel control
module. |
| 2. |
Test for less than 5.0 Ω
between the ground terminal B X3 and ground. |
| ⇒ |
If greater than the specified value, test the
ground circuit for an open/high resistance. |
| 3. |
Ignition ON, verify a test
lamp illuminates between the B+ terminal A X3 and ground.
|
| ⇒ |
If the test lamp does not illuminate, test the
ignition circuit for a short to ground or an open/high
resistance. |
| 4. |
Ignition OFF, connect the X3
harness connector and disconnect the harness connector at the
heated steering wheel control switch. |
| 5. |
Ignition OFF, test for less
than 5.0 Ω between the ground circuit terminal 4 and
ground. |
| ⇒ |
If greater than the specified range, test the
ground circuit for an open/high resistance. |
| 6. |
Ignition ON, test for greater
than 4.8 V between the signal circuit terminal 8 and ground.
|
| ⇒ |
If less than the specified range, test the signal
circuit for a short to ground or open/high resistance. If the
circuit tests normal, replace the heated steering wheel control
module. |
| 7. |
Connect a test lamp between
the control circuit terminal 7 and ground. Verify the test lamp
does not illuminate with the heated steering wheel OFF.
|
| ⇒ |
If the test lamp illuminates, test the control
circuit for a short to voltage. If the circuit tests normal,
replace the heated steering wheel control module. |
| 8. |
Install a 3 A fused jumper
wire between the signal circuit terminal 8 and the ground circuit
terminal 4. Verify the test lamp illuminates. |
| ⇒ |
If the test lamp does not illuminate, test the
control circuit for a short to ground or open/high resistance. If
the circuit tests normal, replace the heated steering wheel control
module. |
| 9. |
If all circuits test normal,
test or replace the heated steering wheel control switch.
|
Heater and Controller Test
| 1. |
Ignition OFF, disconnect the
X1 harness connector at the heated steering wheel. |
| 2. |
Test for less than 5.0 Ω
between the ground circuit listed below and ground. |
| |
• |
Terminal C X1 on the vehicle
harness side |
| |
• |
Terminal D X1 on the vehicle
harness side |
| ⇒ |
If greater than the specified value, test the
ground circuit for an open/high resistance. |
| 3. |
Test for 6000-35000 Ω
between the signal terminal B X1 and the ground terminal C X1 on
the heated steering wheel harness side. |
| ⇒ |
If not within the specified range, replace the
heated steering wheel. |
| 4. |
Test for 1.5-3.0 Ω
between the control circuit terminal A X1 and the ground terminal D
X1 on the heated steering wheel harness side. |
| ⇒ |
If not within the specified range, replace the
heated steering wheel. |
| 5. |
If all circuits test normal,
replace the heated steering wheel control module. |
Component Testing
Heated Steering Wheel Control Switch
| 1. |
Ignition OFF, disconnect the
X3 harness connector at the heated steering wheel control
switch. |
| 2. |
Place the heated steering
wheel control switch in the OFF position. |
| 3. |
Test for infinite resistance
between the ground terminal 4 and the signal terminal 8.
|
| ⇒ |
If less than the specified value, replace the
switch. |
| 4. |
Place the heated steering
wheel control switch in the ON position. |
| 5. |
Test for less than 2 Ω
between ground terminal 4 and signal terminal 8. |
| ⇒ |
If greater than the specified value, replace the
switch. |
Heated Steering Wheel
| 1. |
Ignition OFF, disconnect the
X1 harness connector at the heated steering wheel. |
| 2. |
Test for 6000-35000 Ω
between the signal terminal B X1 and the ground terminal C
X1. |
| ⇒ |
If not within the specified range, replace the
heated steering wheel. |
| 3. |
Test for 1.5-3.0 Ω
between the control circuit terminal A X1 and the ground terminal D
X1. |
| ⇒ |
If not within the specified range, replace the
heated steering wheel. |
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic
procedure.
|
