Driver / Passenger Forward-Sensor Circuit Short to Power Circuit or Open

DTC B1074 / B1078: Driver / Passenger Forward-Sensor Circuit Short to Power Circuit or Open

Wiring Diagram

Refer to Driver / Passenger Forward-Sensor Circuit Short to Ground DTC B1073 / B1077: Driver / Passenger Forward-Sensor Circuit Short to Ground:Except Advanced Air Bag.

DTC Will be Set when

Forward-sensor abnormal signal is detected by SDM.

Flow Test Description

Step 2: Check for open circuit in forward-sensor circuit.

Step 3: Check for short circuit between forward-sensor circuit and power supply circuit.

Step 4: Check if malfunction is in forward-sensor.

DTC Troubleshooting

1.
Was "Air Bag Diagnostic System Check" performed?
YES -
Go to Step 2.
NO -
Go to Air Bag Diagnostic System Check Air Bag Diagnostic System Check:Except Advanced Air Bag.

2. Turn ignition switch to OFF position.
Disconnect forward-sensor connector "E13" or "E24".
Disconnect SDM connector "G47" or "L33".
Check proper connection to SDM connector at terminals "G47-9" and "G47-17" or "L33-9" and "L33-10" (for DTC B1074), or terminals "G47-11" and "G47-19" or "L33-11" and "L33-12" (for DTC B1078).
Check proper connection to forward-sensor connector at terminals "E13-1" and "E13-2" or "E24-1" and "E24-2".
Using service wire (1), connect "E13-1" and "E13-2" terminal (for DTC B1074) or "E24-1" and "E24-2" terminal (for DTC B1078) of forward-sensor connector.
Measure resistance between "G47-9" and "G47-17" (for DTC B1074) or "G47-11" and "G47-19" (for DTC B1078) [A], or between "L33-9" and "L33-10" (for DTC B1074) or "L33-11" and "L33-12" (for DTC B1078) [B].
Special Tool

(A): 09932-76010





Is each measured resistance 1 ohms or less?
YES -
Go to Step 3.
NO -
For DTC B1074: High resistance or open wire in "ORN" circuit or "PNK/BLK" circuit.
For DTC B1078: High resistance or open wire in "PNK" circuit or "PNK/BLU" circuit.

3. Disconnect service wire from "E13" or "E24" connector.
Measure voltage between "G47-9" and body ground, "G47-17" and body ground (for DTC B1074) or "G47-11" and body ground, "G47-19" and body ground (for DTC B1078) [A], or between "L33-9" and body ground, "L33-10" and body ground (for DTC B1074) or "L33-11" and body ground, "L33-12" and body ground (for DTC B1078) [B].
Special Tool

(A): 09932-76010





With ignition switch ON, is each measured value 1 V or less?
YES -
Go to Step 4.
NO -
For DTC B1074: "ORN" circuit or "PNK/BLK" circuit shorted to power circuit.
For DTC B1078: "PNK" circuit or "PNK/BLU" circuit shorted to power circuit.

4. Check forward-sensor referring to Forward-Sensor Inspection Forward-Sensor Inspection:Except Advanced Air Bag.

Is it in good condition?
YES -
Substitute a known-good SDM and recheck.
NO -
Replace forward-sensor referring to Forward-Sensor Removal and Installation Forward-Sensor Removal and Installation:Except Advanced Air Bag. If DTC still exists, substitute a known-good SDM and recheck.

NOTE:

Upon completion of inspection and repair work, perform the following items.

- Reconnect all air bag system components and ensure all components are properly mounted.
- Clear DTCs referring to DTC Clearance DTC Clearance:Except Advanced Air Bag
, if any.
- Repeat Air Bag Diagnostic System Check Air Bag Diagnostic System Check:Except Advanced Air Bag
to confirm that the trouble has been corrected.