Circuit Description
A 5.0 volt reference is supplied to the steering wheel position sensor through the EBCM connector terminal 1 to sensor terminal A. Steering wheel position input to the EBCM is provided through steering wheel position sensor terminal B to the EBCM terminal 17. Steering wheel position sensor ground is provided through the EBCM terminal 5.
Conditions for Setting the DTC
| • | DTC C1243 can set anytime. |
| • | Steering wheel position sensor voltage is less than 0.4 volts or greater than 4.7 volts for 2 seconds or longer. |
| • | Steering wheel position sensor voltage changes by more than 2.5 volts within 8.0 milliseconds. |
Action Taken When the DTC Sets
| • | A malfunction DTC stores. |
| • | VES is disabled and power steering returns to full assist. |
| • | ABS remains functional. |
Conditions for Clearing the DTC
| • | The condition responsible for setting the DTC no longer exists and the Scan Tool Clear DTCs function is used. |
| • | 100 drive cycles pass with no DTCs detected. A drive cycle consists of starting the vehicle, driving the vehicle over 16 km/h (10 mph), stopping and then turning the ignition OFF. |
Diagnostic Aids
The following conditions may cause an intermittent malfunction:
| • | A poor connection |
| • | Rubbed-through wire insulation |
| • | A broken wire inside the insulation |
| • | Open or short in any of the sensor signal circuit wires |
| • | Malfunctioning steering wheel position sensor |
Use the Snapshot function of the Scan Tool to aid in monitoring steering wheel position sensor voltages.
Use the enhanced diagnostic function of the Scan Tool in order to measure the frequency of the malfunction.
Thoroughly inspect any circuitry that may be causing the intermittent complaint for the following conditions:
| • | Backed out terminals |
| • | Improper mating |
| • | Broken locks |
| • | Improperly formed or damaged terminals |
| • | Poor terminal-to-wiring connections |
| • | Physical damage to the wiring harness |
Ensure all ABS DTCs are diagnosed and corrected prior to clearing VES DTCs. Clearing VES DTCs will automatically clear ABS DTCs resulting in a loss of DTC history data.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
|
Important: Zero the J 39200 test leads before making any resistance measurements. Refer to the J 39200 user's manual. Important: Difficulty may occur when trying to locate intermittent malfunctions in the steering wheel position sensor circuit. Do not disturb any of the electrical connections. Change the electrical connections only when instructed to do so by a step in the diagnostic table. | ||||
1 | Was the ABS Diagnostic System Check performed? | -- | Go to Step 2 | |
2 |
Does the voltage vary within the specified range? | 0.4-4.7 V | Go to Step 43 | Go to Step 3 |
3 | Is the voltage from Step 2 less than the specified value? | 0.4 V | Go to Step 5 | Go to Step 4 |
4 | Is the voltage from Step 2 greater than the specified value? | 4.7 V | Go to Step 14 | Go to Step 21 |
5 |
Is the resistance within the specified range? | OL (Infinite) | Go to Step 6 | Go to Step 29 |
6 | Using the J 39200 , measure the resistance between the EBCM harness connector terminals 1 and 5. Is the resistance within the specified range? | OL (Infinite) | Go to Step 7 | Go to Step 30 |
7 | Using the J 39200 , measure the resistance between the EBCM harness connector terminal 17 and ground. Is the resistance within the specified range? | OL (Infinite) | Go to Step 8 | Go to Step 31 |
8 | Using the J 39200 , measure the resistance between the EBCM harness connector terminal 1 and ground. Is the resistance within the specified range? | OL (Infinite) | Go to Step 9 | Go to Step 32 |
9 | Using the J 39200 , measure the resistance between the EBCM harness connector terminal 1 and the steering wheel position sensor harness connector terminal A. Is the resistance within the specified range? | 0-2 ohms | Go to Step 10 | Go to Step 33 |
10 | Using the J 39200 , measure the resistance between the EBCM harness connector terminal 17 and the steering wheel position sensor harness connector terminal B. Is the resistance within the specified range? | 0-2 ohms | Go to Step 11 | Go to Step 34 |
11 | Inspect EBCM harness connector terminals 1 and 17 and all the steering wheel position sensor terminals for poor terminal contact. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. Is poor terminal contact evident? | -- | Go to Step 35 | Go to Step 12 |
12 |
Is the voltage greater than the specified value? | 4.0 V | Go to Step 41 | Go to Step 13 |
13 |
Is DTC C1243 set as a current DTC? | -- | Go to Step 42 | |
14 |
Does the scan tool display the steering wheel position sensor voltage within the specified range? | 0-1.0 V | Go to Step 15 | Go to Step 16 |
15 | Using the J 39200 measure the resistance between the steering wheel position sensor harness connector terminal C and ground. Is the resistance within the specified range? | 0-5.0 ohms | Go to Step 41 | Go to Step 18 |
16 |
Is the voltage within the specified range? | 0-1.0 V | Go to Step 17 | Go to Step 38 |
17 |
Repair damage if evident. Is DTC C1243 set as a current DTC? | -- | Go to Step 42 | |
18 |
Is the resistance within the specified range? | 0-2.0 ohms | Go to Step 19 | |
19 |
Is the voltage within the specified range? | 0-1.0 V | Go to Step 20 | Go to Step 37 |
20 |
Is DTC C1243 set as a current DTC? | -- | Go to Step 42 | |
21 |
Is the voltage greater than the specified value? | 4.7 V | Go to Step 22 | Go to Step 23 |
22 |
Is the voltage greater than the specified value? | 4.7 V | Go to Step 27 | Go to Step 41 |
23 |
Is the resistance within the specified range? | OL (Infinite) | Go to Step 24 | Go to Step 40 |
24 | Using the MIN/MAX function of the J 39200 , measure the resistance between the steering wheel position sensor terminals A and B while rotating the steering wheel slowly from stop-to-stop. Is the resistance within the specified range? | 390-12,000 ohms | Go to Step 25 | Go to Step 41 |
25 |
Is DTC C1243 set as a current DTC? | -- | Go to Step 42 | Go to Step 26 |
26 | Turn the steering wheel slowly from stop-to-stop. Is DTC C1243 set as a current DTC? | -- | Go to Step 41 | |
27 |
Is the voltage greater than the specified voltage? | 1.0 V | Go to Step 39 | Go to Step 28 |
28 |
Is DTC C1243 set as a current DTC? | -- | Go to Step 42 | |
29 | Repair the short between CKTs 1059 and 556. Is the repair complete? | -- | -- | |
30 | Repair the short between CKTs 1056 and 556. Is the repair complete? | -- | -- | |
31 | Repair the short to ground in CKT 1059. Is the repair complete? | -- | -- | |
32 | Repair the short to ground in CKT 1056. Is the repair complete? | -- | -- | |
33 | Repair the open or high resistance in CKT 1056. Is the repair complete? | -- | -- | |
34 | Repair the open or high resistance in CKT 1059. Is the repair complete? | -- | -- | |
35 | Replace the terminals that exhibit poor contact. Is the repair complete? | -- | -- | |
36 | Repair the open or high resistance in CKT 556. Is the repair complete? | -- | -- | |
37 | Repair the short to voltage in CKT 556. Is the repair complete? | -- | -- | |
38 | Repair the short to voltage in CKT 1059. Is the repair complete? | -- | -- | |
39 | Repair the short to voltage in CKT 1056. Is the repair complete? | -- | -- | |
40 | Repair the short between CKTs 1056 and 1059. Is the repair complete? | -- | -- | |
41 | Replace the Steering Wheel Position Sensor. Refer to Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement . Is the repair complete? | -- | -- | |
42 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement in Brakes. Is the repair complete? | -- | -- | |
43 | The malfunction is intermittent or not present at this time. Refer to Diagnostic Aids for more information. Is the action complete? | -- | System OK | -- |
