DTC C1139:64 [DYNAMIC STABILITY CONTROL (DSC)]

id0402b2848900

DTC
C1139:64
AUTOHOLD switch
DETECTION CONDITION
•  Continuous ON signal from the AUTOHOLD switch for 30 s or more is detected.
FAIL-SAFE FUNCTION
Refer to “DTC Table” and “Fail-safe function table”. (See DTC TABLE [DYNAMIC STABILITY CONTROL (DSC)].)
POSSIBLE CAUSE
Caution
•  When the AUTOHOLD switch is continuously pressed down for a long period, DTCs may be detected. Therefore, always verify that DTCs being detected are due to how the customer has operated the switch.
•  Short to ground in the wiring harness between the electric parking brake control module terminal 2D and AUTOHOLD switch terminal D
•  AUTOHOLD switch malfunction
―  AUTOHOLD switch is mechanically stuck
•  Electric parking brake control module malfunction
SYSTEM WIRING DIAGRAM
Not applicable

Diagnostic Procedure

STEP

INSPECTION

ACTION
1
ASK CUSTOMER IF AUTOHOLD SWITCH HAS BEEN PRESSED DOWN CONTINUOUSLY FOR 30 S OR MORE
•  Ask the customer if the AUTOHOLD switch has been pressed down continuously for 30 s or more.
•  Has the AUTOHOLD switch been pulled up/pressed down continuously for 30 s or more?
Yes
System is normal. (Explain to the customer that it is not necessary to continuously press down the AUTOHOLD switch to operate/release the AUTOHOLD system.)
No
Go to the next step.
2
INSPECT AUTOHOLD SWITCH
•  Visually verify the AUTOHOLD switch for the following.
―  Interference with surrounding parts
―  Foreign matter penetration in movable parts
•  Is the AUTOHOLD switch normal?
Yes
Go to the next step.
No
Interference with surrounding parts:
•  Install the AUTOHOLD switch correctly.
―  If the malfunction recurs, replace the AUTOHOLD switch.
•  Go to the next step.
Foreign matter has penetrated movable parts:
•  Remove the foreign matter, then go to the next step.
3
INSPECT AUTOHOLD SWITCH SIGNAL CIRCUIT FOR SHORT TO GROUND
•  Disconnect the AUTOHOLD switch.
•  Disconnect the electric parking brake control module connector.
•  Inspect for continuity between the AUTOHOLD switch connector terminal D (vehicle harness-side) and body ground.
•  Is there continuity?
Yes
Repair or replace the wiring harness, then go to the next step.
No
Go to the next step.
4
VERIFY THAT REPAIRS HAVE BEEN COMPLETED
•  Clear the DTC for the DSC HU/CM using the M-MDS.
•  Perform the following procedure 3 times or more.
―  Press down the AUTOHOLD switch to release the autohold.
•  Retrieve the DSC HU/CM DTCs using the M-MDS.
•  Is the same DTC displayed?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the electric parking brake control module.
Go to the next step.
No
Go to the next step.
5
VERIFY IF OTHER DTCs DISPLAYED
•  Are any other DTCs displayed?
Yes
Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.
(See DTC TABLE [DYNAMIC STABILITY CONTROL (DSC)].)
No
DTC troubleshooting completed.