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 DTC C1955, C1956 [DSC]

DTC C1955, C1956 [DSC]

id040220875400

DTC

C1955, C1956

Steering angle sensor

DETECTION CONDITION

• C1955:
- Output voltages from steering angle sensors 1 and 2 are not at 1 V or less, or not at 3.25 V or more
• C1956:
- Sensor 1 voltage remains unchanged, sensor 2 voltage changes
- Sensor 2 voltage remains unchanged, sensor 1 voltage changes
- When steering wheel is turned in specified direction, neutral position is detected even when rotated at 18 degrees or more

POSSIBLE CAUSE

• Open circuit in harness between steering angle sensor terminal A and ignition switch
• Open, short to power, or short to ground circuit in harness between DSC HU/CM terminal X and steering angle sensor terminal B
• Open, short to power, or short to ground circuit in harness between DSC HU/CM terminal W and steering angle sensor terminal C
• Open, short to power, or short to ground circuit in harness between DSC HU/CM terminal U and steering angle sensor terminal D
• Open circuit in harness between DSC HU/CM terminal Rand steering angle sensor terminal F
• Malfunction of steering angle sensor

Diagnostic procedure

STEP

INSPECTION

ACTION

1
INSPECT STEERING ANGLE SENSOR POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT
• Turn ignition key to ON (engine OFF).
• Measure voltage between steering angle sensor terminal A (harness side) and ground.
• Is voltage B+?
Yes
Go to next step.
No
Repair or replace harness for open circuit between steering angle sensor terminal A and ignition switch, then go to Step 7.
2
INSPECT STEERING ANGLE SENSOR GROUND CIRCUIT FOR OPEN CIRCUIT
• Turn ignition key to OFF.
• Disconnect DSC HU/CM and steering angle sensor connectors.
• Inspect continuity between DSC HU/CM terminal R (harness side) and steering angle sensor terminal F (harness side).
• Is there continuity?
Yes
Go to next step.
No
Repair or replace harness for open circuit between DSC HU/CM terminal R and steering angle sensor terminal F, then go to Step 7.
3
INSPECT STEERING ANGLE SENSOR SIGNAL CIRCUIT FOR OPEN CIRCUIT
• Inspect continuity between DSC HU/CM terminal (harness side) and steering angle sensor terminal (harness side) below.
- Sensor 1: DSC HU/CM X and steering angle sensor B
- Sensor 2: DSC HU/CM W and steering sensor C
- Neutral: DSC HU/CM U and steering angle sensor D
• Is there continuity?
Yes
Go to next step.
No
Repair or replace harness for open circuit between DSC HU/CM terminal and steering angle sensor terminal, then go to Step 7.
4
INSPECT STEERING ANGLE SENSOR SIGNAL CIRCUIT FOR SHORT TO POWER
• Turn ignition key to ON (engine OFF).
• Measure voltage between DSC HU/CM terminal (harness side) and ground below.
- Sensor 1: DSC HU/CM X and ground
- Sensor 2: DSC HU/CM W and ground
- Neutral: DSC HU/CM U and ground
• Is voltage B+?
Yes
Repair or replace harness for short to power circuit between DSC HU/CM terminal and steering angle sensor terminal, then go to Step 7.
No
Go to next step.
5
INSPECT STEERING ANGLE SENSOR SIGNAL CIRCUIT FOR SHORT TO GROUND
• Turn ignition key to OFF.
• Inspect continuity between DSC HU/CM terminal (harness side) and ground below.
- Sensor 1: DSC HU/CM X and ground
- Sensor 2: DSC HU/CM W and ground
- Neutral: DSC HU/CM U and ground
• Is there continuity?
Yes
Repair or replace harness for short to ground circuit between DSC HU/CM terminal and steering angle sensor terminal, then go to Step 7.
No
Go to next step.
6
INSPECT STEERING ANGLE SENSOR
• Inspect steering angle sensor.
• Is it normal?
Yes
Go to next step.
No
Replace steering angle sensor, then go to next step.
7
VERIFY TROUBLESHOOTING COMPLETED
• Clear DTC from memory.
• Is the same DTC present?
Yes
Replace DSC HU/CM, then go to next step.
No
Go to next step.
8
VERIFY THAT NO OTHER DTCS ARE PRESENT
• Are any other DTCs output?
Yes
Go to the applicable DTC inspection.
(See DTC Table.)
No
DTC troubleshooting completed.