DTC Advanced Diagnostics: C1040-00
DTC C1040-00: Different Diameter Tire is Detected
NOTE
Initial Diagnosis:
The initial on-board diagnosis occurs right after the vehicle condition is turned to the ON mode, and the ABS/VSA indicator comes on, and continues until the indicator goes off.
Regular Diagnosis:
The regular on-board diagnosis begins right after the ABS/VSA indicator goes off, and it continues until the vehicle condition is turned to the OFF (LOCK) mode.
Review "How to troubleshoot the VSA system" before doing the DTC troubleshooting procedure.
Test-drive the vehicle according to local traffic conditions and regulations. Do not test-drive on a lift unless specified.
The possible causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

Confirmation Procedure
Basic Condition:
No other DTCs detected

With the Driving Pattern:
1.
Start the engine.
2.
Test-drive the vehicle at 12 mph (20 km/h) or more for at least 72 seconds.
(Be careful of the surrounding traffic conditions.)
Execution
Regular Diagnosis
Duration
About 72 seconds
DTC Type
1 drive cycle
Brake system indicator (red) on (Dependant upon the conditions)
Brake system indicator (amber) on
ABS indicator on
VSA indicator on
Fail Safe Action
Stop EBD function (Dependant upon the conditions)
Stop ABS function
Stop engine drag torque control function
Stop TCS function
Stop VSA function
Stop agile handling assist control function
Stop brake assist function
Stop hydraulic boost failure compensation function
Stop hill start assist function
Stop automatic brake hold function
Stop automatic operating function (Drive away assist)
Stop automatic operating function (Request from other system) (Dependant upon the conditions)
Stop ignition OFF apply function
Stop ACC function*
Stop CMBS function*
Possible Cause
Low air pressure in tires
Different diameter tires
Wheel speed sensor failure
Debris on the encoder surface
VSA modulator-control unit internal failure
*: With ACC