DTC B1870

• The air bag system warning light is designed to illuminate for approx. 6 s when the ignition switch is turned to the ON position. This initial 6 s 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.

STEP	INSPECTION		ACTION
1	Turn the ignition switch to the LOCK position. Connect the M-MDS. Turn the ignition switch to the ON position. Using the M-MDS, 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.
1		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 AIR BAG SYSTEM SERVICE WARNINGS.) (See AIR BAG SYSTEM 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.
2		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. Note • Measure the resistance while shaking the wiring harness between the SAS control module and instrument cluster. Is the resistance less than 10,000 ohms?	Yes	Repair the related wiring harness. After repair, go to Step 5.
3		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.
4		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.
5		No	Refer to the reactivation procedure in the air bag system deactivation procedure, reactivate the system. Clear all DTCs.