DTC B1870

id080200803500

System Malfunction Location

• Air bag system warning light circuit short to power supply

Detection Condition

Warning
• Detection conditions are for understanding the DTC outline before performing an inspection. Performing an inspection according to only the detection conditions may cause injury due to an operating error, or damage the system. When performing an inspection, always follow the inspection procedure.

• The air bag system warning light is designed to illuminate for 6 (±2) seconds when the ignition switch is turned to the ON position. This initial 6 seconds of illumination is considered normal operation. The air bag indicator is then used to warn the driver if there is a malfunction in the air bag system. The SAS control module monitors the air bag system warning light circuit for short to power supply. If the SAS control module detects a short to power supply on the air bag system warning light circuit, it will store DTC B1870 in memory. If the SAS control module detects an air bag system warning light malfunction in addition to another air bag system malfunction, the SAS control module will send a signal to the instrument cluster to produce five sets of five tone chimes.

Possible Cause

• Short to power supply between the instrument cluster and the SAS control module

• Instrument cluster malfunction

• SAS control module internal malfunction

Diagnostic Procedure

STEP

INSPECTION

ACTION

1
Turn the ignition switch to the LOCK position.
Connect the WDS or the equivalent.
Turn the ignition switch to the ON position.
Using the WDS or equivalent, verify the DTCs and record the past malfunction DTCs.
Is the present malfunction DTC B1870 displayed?
Yes
Note
• Indicates a hard malfunction. The malfunction is still present. This malfunction cannot be cleared until it is corrected and the DTC is no longer displayed.
Go to the next step.
No
Intermittent malfunction. The malfunction is not present at this time. Go to Step 5.
2
Warning
• Handling the components improperly can accidentally deploy the air bags and pre-tensioner front buckle, which may seriously injure you. Read the service warnings and cautions before handling the SRS air bag system components.
(See SERVICE WARNINGS.)
(See SERVICE CAUTIONS.)
Turn the ignition switch to the LOCK position.
Refer to the air bag system deactivation procedure and deactivate the system.
Disconnect the SAS control module connectors.
Turn the ignition switch to the ON position.
Does the air bag system warning light illuminate?
Yes
Go to the next step.
No
Inspect the air bag system warning light bulb. If the bulb is normal, repair or replace the related wiring harness. After repair or replacement, go to Step 5.
3
Turn the ignition switch to the LOCK position.
Disconnect the instrument cluster connector.
Disconnect the negative battery cable.
Turn the ignition switch to the ON position.
Measure the resistance between SAS control module terminal 2V and 2T.
Is the resistance less than 10,000 ohms?
Yes
Repair the related wiring harness. After repair, go to Step 5.
No
Replace the instrument cluster. (See INSTRUMENT CLUSTER REMOVAL/INSTALLATION.)
After replacement, go to Step 5.
4
Refer to the past malfunction DTCs recorded during Step 1.
Are the past malfunction DTCs displayed during Step 1 intermittent malfunctions which are not displayed as present malfunction DTCs?
Yes
Inspect for an intermittent short to power supply between the instrument cluster and the SAS control module. Attempt to replicate the malfunction by flexing the wiring harness and cycling the ignition key between the ON and LOCK position repeatedly. Repair or replace if there is any intermittent malfunction.
After repair or replacement, go to the next step.
No
Go to the next step.
5
Refer to the past malfunction DTCs recorded during Step 1.
Was any past malfunction DTC displayed during Step 1?
Yes
If any DTC is displayed, refer to the DTC table, and repair the malfunctioning part according to the DTC inspection.
No
Refer to the reactivation procedure in the air bag system deactivation procedure, reactivate the system. Clear all DTCs.