C1348 Difference in the size between the front and rear tires is detected

DESCRIPTION

The skid control ECU measures the speed of each wheel by receiving signals from the speed sensors. These signals are used to recognize that all 4 wheels are operating properly. Therefore, all wheel signals must be equal.

DTC No.	DTC Detection Condition	Trouble Area
C1348	Difference in the size between the front and rear tires is detected	Tire size Tire pressure Speed sensor circuit Skid control ECU

WIRING DIAGRAM

(Click here) for front circuit.
(Click here) for rear circuit.

INSPECTION PROCEDURE

1. CHECK DTC

1. Check the output DTC (axle system, brake control system, CAN communication system).
   

   Result:

   Result	Proceed to
   DTC C1348 only is output	A
   CAN communication DTC is output	B
   Brake control system DTC is output	B

   HINT:

   When DTCs indicating a CAN communication system malfunction are output, repair the CAN communication system before repairing each corresponding sensor.

B	REPAIR CIRCUIT INDICATED BY OUTPUT CODE

A

2. CHECK TIRE CONDITION

1. Check the size and condition of all 4 tires (Click here).

   HINT:

   This DTC is output when tire deformation or a difference in tire sizes is detected.

   OK:

   The diameter and air pressure of all 4 tires are the same.
   

NG	REPLACE TIRES SO THAT ALL 4 TIRE ARE THE SAME IN SIZE, OR ADJUST TIRE PRESSURE

OK

3. READ VALUE OF INTELLIGENT TESTER

1. Connect the intelligent tester to the DLC3.

2. Start the engine.

3. Select the "Data List" on the intelligent tester (Click here).

4. Drive the vehicle several times and check that the speed values detected at all 4 wheels displayed on the intelligent tester are the same.

   Data List: ABS/TRC/VSC 

   Item	Measurement Item / Range (Display)	Normal Condition
   FR Wheel Speed	Wheel speed sensor (FR) reading / min.: 0 km/h (0 mph), max.: 326.4 km/h (202 mph)	Actual wheel speed
   FL Wheel Speed	Wheel speed sensor (FL) reading / min.: 0 km/h (0 mph), max.: 326.4 km/h (202 mph)	Actual wheel speed
   RR Wheel Speed	Wheel speed sensor (RR) reading / min.: 0 km/h (0 mph), max.: 326.4 km/h (202 mph)	Actual wheel speed
   RL Wheel Speed	Wheel speed sensor (RL) reading / min.: 0 km/h (0 mph), max.: 326.4 km/h (202 mph)	Actual wheel speed

   OK:

   The vehicle speed detected at all 4 wheels must be indicated on the intelligent tester.
   

NG	CHECK SPEED SENSOR CIRCUIT (BRAKE CONTROL SYSTEM)

OK

4. RECONFIRM DTC

1. Clear the DTC (Click here).

2. Turn the ignition switch off.

3. Start the engine.

4. Drive the vehicle several times at the speed of 30 km/h (18 mph) or more and check that same DTC is output.
   

   Result:

   Result	Proceed to
   DTC (C1348) is output	A
   DTC (C1348) is not output	B

B	END

A
REPLACE SKID CONTROL ECU