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For 1990-2009 cars only

Vehicle Stability Enhancement System Unwanted Activation w/JL4


Object Number: 456438  Size: MF
ABS Components
Vehicle Stability Enhancement System (w/JL4)
Handling ESD Sensitive Parts Notice

Circuit Description

When the vehicle stability enhancement system (VSES) or TCS activates for longer than 1.5 seconds, there will be an accompanying DIC message. Short activations of either system may occur without any DIC messages. The VSES activations mostly occur in the turns or bumpy roads without much use of the accelerator pedal. Activations may also occur during aggressive driving. Unwanted VSES activations may be caused by the following:

    • A loosely mounted yaw rate sensor
    • An intermittent faulty steering wheel position sensor
    • An intermittent wiring harness problem
    • A chassis alignment that is grossly out of specification
    • The wrong EBCM installed
    • The wrong steering gear rack installed

Step

Action

Value(s)

Yes

No

1

Did you perform the ABS Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - ABS

2

Inspect the mounting of the yaw rate sensor. Refer to Vehicle Yaw Sensor Replacement .

Did you find and correct the condition?

--

Go to Step 15

Go to Step 3

3

  1. Install a scan tool.
  2. Start the engine.
  3. With a scan tool, observe the Yaw Rate Sensor Input parameter in the VSES data list.
  4. Perform the Diagnostic Test Drive. Refer to Diagnostic Test Drive .

Does the scan tool display suddenly increase or decrease without rapid turning of the vehicle?

--

Go to Step 4

Go to Step 5

4

Perform the diagnosis for DTC C1282. Refer to DTC C1282 Yaw Rate Sensor Bias Circuit Malfunction .

Did you find and correct the condition?

--

Go to Step 15

Go to Step 12

5

  1. Straighten the front wheels.
  2. Observe the Dual Analog SWPS Input A and Dual Analog SWPS Input B in he VSES data list.
  3. Slowly rotate the steering wheel in both directions.

Does the scan tool display change states as the steering wheel was rotated?

--

Go to Step 6

Go to Step 14

6

Use the scan tool in order to perform the Steering Position Sensor Test in the DRP/ABS/TCS/TIM/VSES Special Functions. Refer to Scan Tool Diagnostics .

Did the steering wheel position sensor (SWPS) pass the test?

--

Go to Step 7

Go to Step 14

7

  1. Place the vehicle on a level surface.
  2. With a scan tool, observe the Lateral Accelerometer Input parameter in the VSES data list.

Does the scan tool display within the specified range?

2.3-2.7 V

Go to Step 9

Go to Step 8

8

Inspect the mounting of the lateral accelerometer sensor. Refer to Lateral Accelerometer Replacement .

Did you find and correct the condition?

--

Go to Step 15

Go to Step 9

9

Inspect the EBCM for the proper part number.

Did you find the correct part number?

--

Go to Step 10

Go to Step 12

10

Inspect the power steering gear for the proper part number.

Did you find the correct part number?

--

Go to Step 11

Go to Step 13

11

Inspect the alignment of the vehicle. Refer to Preliminary Alignment Inspection in Wheel Alignment.

Did you find and correct the condition?

--

Go to Step 15

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

12

Important: Perform the setup procedure for the EBCM. An unprogrammed EBCM will result in the following conditions:

   • Inoperative or poorly functioning DRP/ABS/TCS/TIM/VSES/VES (if equipped)
   • Set DTC C1248 EBCM Turned the Red Brake Warning Indicator On
   • Set DTC C1255m3 EBCM Internal Malfunction

Replace the EBCM. Refer to Electronic Brake Control Module Replacement .

Did you complete the replacement?

--

Go to Step 15

--

13

Replace the power steering gear. Refer to Steering Gear Replacement in Power Steering System.

Did you complete the replacement?

--

Go to Step 15

--

14

Replace the steering wheel position sensor (SWPS). Refer to Steering Shaft, Lower Bearing, and Jacket - Disassemble - Off Vehicle and Steering Shaft, Lower Bearing, and Jacket - Assemble - Off Vehicle in Steering Wheel and Column - Tilt

Did you complete the replacement?

--

Go to Step 15

--

15

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2