DTC C1040-00 (VSA Control Unit)

DTC C1040-00  : Different Diameter Tire is Detected

NOTE: Before you troubleshoot, review the general troubleshooting information .

DTC Description	DTC
C1040-00 Different Diameter Tire is Detected

DTC (VSA)

1. Problem verification

   -1. Turn the vehicle to the ON mode.

   -2. Clear the DTC with the HDS.

   -3. Turn the vehicle to the OFF (LOCK) mode, then to the READY TO DRIVE mode.

   -4. Test-drive the vehicle at 12 mph (20 km/h) or more for at least 72 seconds.

   NOTE:  Drive the vehicle on the road, not on a lift.

   -5. Check for DTCs with the HDS.

   DTC Description	DTC
   C1040-00 Different Diameter Tire is Detected

   Is DTC C1040-00 indicated?

   YES 

   The failure is duplicated. Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time. Refer to intermittent failures troubleshooting .

2. Tire check

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Check all four tires for size, inflation, and wear .

   Are all four tires the correct size, properly inflated, and worn evenly?

   YES 

   Go to step 3.

   NO 

   Swap the wheels and tires with a known-good set (the correct size, type, and properly inflated), then retest-drive the vehicle.

3. Wheel speed sensor performance check

   -1. Test-drive the vehicle at 12 mph (20 km/h) or more in a straight line.

   NOTE:  Drive the vehicle on the road, not on a lift.

   -2. Check the parameter(s) below with the HDS.

   Signal	Current conditions
   	Values	Unit
   RIGHT FRONT WHEEL SPEED
   LEFT FRONT WHEEL SPEED
   RIGHT REAR WHEEL SPEED
   LEFT REAR WHEEL SPEED

   Is any one of the four values different?

   YES 

   Go to step 4.

   NO 

   Check for loose terminals and poor connections in the VSA modulator-control unit 46P connector. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting. If they are OK, replace the VSA modulator-control unit .

4. Wheel speed sensor check

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Substitute a known-good wheel speed sensor .

   -3. Turn the vehicle to the ON mode.

   -4. Clear the DTC with the HDS.

   -5. Turn the vehicle to the OFF (LOCK) mode, then to the READY TO DRIVE mode.

   -6. Test-drive the vehicle at 12 mph (20 km/h) or more for at least 72 seconds.

   NOTE:  Drive the vehicle on the road, not on a lift.

   -7. Check for DTCs with the HDS.

   DTC Description	DTC
   C1040-00 Different Diameter Tire is Detected

   Is DTC C1040-00 indicated?

   YES 

   Go to step 5.

   NO 

   Replace the original wheel speed sensor .

5. Magnetic encoder check

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Inspect the magnetic encoder for damage, debris, and correct installation.

   Appropriate Magnetic Encoder	Note
   Left-front	Remove the driveshaft outboard joint from the appropriate wheel hub .
   Right-front
   Left-rear	Remove the hub bearing unit .
   Right-rear

   Is the magnetic encoder surface OK?

   YES 

   Check for loose terminals and poor connections in the VSA modulator-control unit 46P connector. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting. If they are OK, replace the VSA modulator-control unit .

   NO 

   Clean the debris from the appropriate magnetic encoder surface on the wheel bearing or the hub bearing unit. If the debris cannot be removed or the encoder is damaged, replace the appropriate wheel bearing or the hub bearing unit .