Rear Airbag Sensor Left harness is open or shorted
Rear Airbag Sensor Left circuit poor electrical connection
Faulty Center Airbag Sensor Assembly
|How to Fix the B1638 Code?
Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.
The cost to diagnose the B1638 code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.
The Side Collision Sensor Left (LH) circuit (to determine deployment of the Curtain Shield Airbag Assembly LH) is composed of the Center Airbag Sensor Assembly, Side Airbag Sensor LH, and Rear Airbag Sensor LH. The Rear Airbag Sensor LH detects impacts to the vehicle and sends signals to the Center Airbag Sensor Assembly to determine if the airbag should be deployed. The Diagnostic Trouble Code (DTC) is stored when a malfunction is detected for the rear side collision LH circuit (to determine deployment of the Curtain Shield Airbag Assembly LH).
B1638 Code - Rear Airbag Sensor Assembly Left Initialization Incomplete
Precautions for SRS “AIR BAG” and “SEAT BELT PRE-TENSIONER” Service
Never probe the electrical connectors on air bag, side air curtain modules or seat belts.
Never disassemble or tamper with safety belt buckle/retractor pretensioners, adaptive load limiting retractors, safety belt inflators, or probe the electrical connectors.
Do not use electrical test equipment to check SRS circuits unless instructed to in this Service Manual.
Before servicing the SRS, turn ignition switch OFF, disconnect both battery cables and wait at least 3 minutes. For approximately 3 minutes after the cables are removed,
it is still possible for the air bag and seat belt pre-tensioner to deploy. Therefore, do not work on any SRS connectors or wires until at least 3 minutes have passed.
Failure to follow this instruction may result in the accidental deployment of these modules, which increases the risk of serious personal injury or death.