Pinpoint Test G: DTC C1277 And C1278- Steering Wheel Angle 1 And 2 Circuit Failure/Faulted

WARNING: This page is about a different car, the 2004 Mercury Mountaineer and 2004 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION: Use the flex probe kit for all test connections to prevent damage to the wiring terminals. Do not use standard multimeter probes.

G1 CARRY OUT THE RECALIBRATION PROCEDURE
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: Clear the DTCs.
- Carry out the steering position sensor recalibration procedure following the diagnostic tool directions.
- Enter the following diagnostic mode on the diagnostic tool: Retrieve DTCs.
- Are any DTCs retrieved or does the recalibration procedure indicate a fault?
Yes

If DTC C1277 or C1278 is retrieved or the recalibration procedure indicates a fault, GO to G2.

If any other DTCs are retrieved, GO to the ANTI-LOCK BRAKE SYSTEM (ABS) MODULE DIAGNOSTIC TROUBLE CODE (DTC) INDEX .

If sent here from PINPOINT TEST Q , GO TO G2

NO

The ABS System Is Operating Correctly.
G2 Monitor The Steering Position Sensor PIDs
- Make sure the steering wheels are centered straight forward.
- Enter the following diagnostic mode on the diagnostic tool: ABS module PIDs.
- Monitor the ABS module steering position sensor PID while rotating the steering wheel clockwise and counterclockwise.
- Are the two PID values similar?
Yes

Clear the DTCS. Drive the vehicle. Retrieve the DTCS. If DTC C1277 is present, install a new ABS control module. refer to ANTI-LOCK BRAKE SYSTEM (ABS) MODULE . Recalibrate the ABS module. FOLLOW the diagnostic tool directions for the calibration procedure.

No

If the value is less than 360, GO to G3

If the value is greater than 360, REFER to SUSPENSION SYSTEM-GENERAL INFORMATION or STEERING SYSTEM for a suspension or alignment concern. CLEAR the DTCs. REPEAT the self-test.
G3 CHECK CIRCUIT 1003 (GY/YE) FOR AN OPEN
- Key in OFF position.
- Disconnect: Steering Position Sensor C226.
- Key in ON position.
- Measure the voltage between the steering position sensor C226-1, circuit 1003 (GY/YE), harness side, and ground.
  
  Fig 1: Measuring Voltage Between Steering Position Sensor C226-1, Circuit 1003 (GY/YE)
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
Yes

GO to G4.

No

REPAIR the circuit. CLEAR the DTCs. RECALIBRATE the ABS module. FOLLOW the diagnostic tool directions for the calibration procedure. REPEAT the self-test.

G4 CHECK THE STEERING POSITION SENSOR CIRCUITRY FOR AN OPEN

Key in OFF position.
Disconnect: ABS Module C155.

Measure the resistance between the ABS module connector, harness side and the steering position sensor connector, harness side as follows:

CIRCUIT SPECIFICATION

Steering Position Sensor Connector-Pin	ABS Module Connector-Pin	Circuit
C226-2	C155-6	1573 (YE)
C226-3	C155-3	1572 (DG)
C226-4	C155-5	1571 (BK)/1577 (RD/LB)

Fig 2: Measuring Resistance Between ABS Module Connector, Harness Side

Courtesy of FORD MOTOR CO.

Are the resistances less than 5 ohms?

Yes

GO to G5.

REPAIR the circuit(s) in question. CLEAR the DTCs. RECALIBRATE the ABS module. FOLLOW the diagnostic tool directions for the calibration procedure. REPEAT the self-test.

G5 CHECK THE STEERING POSITION SENSOR CIRCUITS FOR A SHORT TO POWER

Key in ON position.

Measure the voltage between the ABS module connector, harness side and ground as follows:

CIRCUIT SPECIFICATION

ABS Module Connector-Pin	Circuit
C155-6	1573 (YE)
C155-3	1572 (DG)
C155-5	1577 (RD/LB)

Fig 3: Measuring Voltage Between ABS Module Connector, Harness Side And Ground

Courtesy of FORD MOTOR CO.

Is any voltage present?

Yes

REPAIR the circuit(s) in question. CLEAR the DTCs. RECALIBRATE the ABS module. FOLLOW the diagnostic tool directions for the calibration procedure. REPEAT the self-test.

GO to G6.

G6 CHECK THE STEERING POSITION SENSOR CIRCUITRY FOR A SHORT TO GROUND

Key in OFF position.

Measure the resistance between the ABS module connector, harness side and ground as follows:

CIRCUIT SPECIFICATION

ABS Module Connector-Pin	Circuit
C155-6	1573 (YE)
C155-3	1572 (DG)
C155-5	1577 (BK)

Fig 4: Measuring Resistance Between ABS Module Connector, Harness Side And Ground

Courtesy of FORD MOTOR CO.

Are the resistances greater than 10,000 ohms?

Yes

INSTALL a new clockspring. REFER to AIR BAG RESTRAINT SYSTEMS . CLEAR the DTCs. REPEAT the self-test.

REPAIR the circuit in question. CLEAR the DTCs. RECALIBRATE the ABS module. FOLLOW the diagnostic tool directions for the calibration procedure. REPEAT the self-test.