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 DTC C1949, C1950 [DSC]

DTC C1949, C1950 [DSC]

id040220875200

DTC

C1949, C1950

Combined sensor (forward G-sensor)

DETECTION CONDITION

• C1949:
- Monitor voltage of forward-G sensor is detected at 4.5 V or more, or 0.5 V or less
- Monitor voltage difference of 0.4 V or more within 1 cycle is detected 8 times in 1 s
• C1950:
- Forward-G sensor 0-point correction value is default or more
- Output voltage value from G sensor remains absolutely unchanged
- Difference between estimated G-force calculated from 2 channels exceeds specification

POSSIBLE CAUSE

• Open circuit in harness between combined sensor terminal C and DSC HU/CM terminal P
• Open circuit, short to power, or short to ground in harness between DSC HU/CM terminal V and combined sensor terminal A
• Open circuit, short to power, or short to ground in harness between DSC HU/CM terminal S and combined sensor terminal F
• Open circuit in harness between combined sensor terminal E and DSC HU/CM terminal Y
• Malfunction of combined sensor

Diagnostic procedure

STEP

INSPECTION

ACTION

1
INSPECT COMBINED SENSOR POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT
• Turn ignition key to ON (engine OFF).
• Measure voltage between combined sensor terminal C (harness side) and ground.
• Is voltage 4.5-5.5 V?
Yes
Go to next step.
No
Repair or replace harness for open circuit between combined sensor terminal C and ignition switch, then go to Step 8.
2
INSPECT COMBINED SENSOR GROUND CIRCUIT FOR OPEN CIRCUIT
• Turn ignition key to OFF.
• Disconnect DSC HU/CM and combined sensor connectors.
• Inspect continuity between DSC HU/CM terminal Y (harness side) and combined sensor terminal E (harness side).
• Is there continuity?
Yes
Go to next step.
No
Repair or replace harness for open circuit between DSC HU/CM terminal Y and combined sensor terminal E, then go to Step 8.
3
INSPECT FORWARD-G SENSOR PART SIGNAL CIRCUIT FOR OPEN CIRCUIT
• Inspect continuity between DSC HU/CM terminal V (harness side) and combined sensor terminal A (harness side).
• Is there continuity?
Yes
Go to next step.
No
Repair or replace harness for open circuit between DSC HU/CM terminal V and combined sensor terminal A, then go to Step 8.
4
INSPECT FORWARD-G SENSOR PART SIGNAL CIRCUIT FOR SHORT TO GROUND
• Turn ignition key to OFF.
• Inspect continuity between DSC HU/CM terminal V (harness side) and ground.
• Is there continuity?
Yes
Repair or replace harness for short to ground circuit between DSC HU/CM terminal V and combined sensor terminal A, then go to Step 8.
No
Go to next step.
5
INSPECT DIAGNOSIS SIGNAL CIRCUIT FOR SHORT FOR OPEN CIRCUIT
• Turn ignition key to OFF.
• Inspect continuity between DSC HU/CM terminal S (harness side) and combined sensor terminal F.
• Is there continuity?
Yes
Repair or replace harness for open circuit between DSC HU/CM terminal S and combined sensor terminal F, then go to Step 8.
No
Go to next step.
6
INSPECT DIAGNOSIS SIGNAL CIRCUIT FOR SHORT TO GROUND
• Turn ignition key to OFF.
• Inspect continuity between DSC HU/CM terminal S (harness side) and ground.
• Is there continuity?
Yes
Repair or replace harness for short to ground circuit between DSC HU/CM terminal S and combined sensor terminal F, then go to Step 8.
No
Go to next step.
7
INSPECT COMBINED SENSOR
• Inspect combined sensor.
• Is it normal?
Yes
Go to next step.
No
Replace combined sensor, then go to next step.
8
VERIFY TROUBLESHOOTING COMPLETED
• Clear DTC from memory.
• Is same DTC present?
Yes
Replace DSC HU/CM, then go to next step.
No
Go to next step.
9
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.