What Does B1216 Mean?
This code indicates the Body Control Module (BCM) has detected a short to ground in the emergency or roadside assistance switch circuit. The system continuously monitors the switch circuit for proper voltage and resistance, and when voltage drops below the expected threshold due to a short to ground, this code is set. This affects the vehicle's emergency communication system that allows occupants to contact emergency services or roadside assistance.
Common Causes
45%
Damaged or chafed wiring harness causing short to ground between BCM and emergency switch
30%
Failed emergency assistance switch with internal short to ground
15%
Corroded or moisture-contaminated connector terminals creating ground path
10%
Failed Body Control Module with internal circuit fault
Diagnostic Steps
1
Step 1: Perform visual inspection of emergency assistance switch, typically located in overhead console or near rearview mirror. Check for physical damage, moisture intrusion, or signs of switch damage
2
Step 2: Disconnect the emergency assistance switch connector and use a digital multimeter to measure resistance between the switch signal wire and ground. Reading should be infinite (open circuit); any continuity indicates a short to ground in wiring or switch
3
Step 3: With switch disconnected, check resistance from BCM connector terminal for emergency switch circuit to ground. Infinite resistance confirms switch is faulty; continuity indicates wiring harness short to ground between BCM and switch
4
Step 4: Inspect wiring harness routing from switch to BCM, paying special attention to areas where harness passes through metal panels, near sharp edges, or pinch points. Look for chafed insulation or crushed wires
5
Step 5: If wiring and switch test good, perform BCM voltage supply test at switch connector with key on. Should read battery voltage on power supply wire. No voltage indicates BCM internal fault or power supply issue
6
Step 6: Clear codes, reconnect all components, and perform operational test of emergency assistance system. Monitor live data for switch circuit voltage while operating switch to verify proper operation and confirm repair
Estimated Repair Cost
$150 - $650
Parts + labor, varies by vehicle and location
This code indicates the Body Control Module (BCM) has detected a short to ground in the emergency or roadside assistance switch circuit. The system continuously monitors the switch circuit for proper voltage and resistance, and when voltage drops below the expected threshold due to a short to ground...
The most common cause of B1216 (Emergency & Road Side Assistance Switch Circuit Short to Ground) is: Damaged or chafed wiring harness causing short to ground between BCM and emergency switch
Typical repair costs for B1216 range from $150 to $650, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Vehicle is safe to drive, but the emergency assistance feature will be non-functional, preventing occupants from contacting emergency services or roadside assistance through the vehicle's communication system in the event of an emergency. Repair should be completed within a reasonable timeframe to restore this important safety feature.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1216 to identify the root cause.
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Quick Info
Category
Body
System
Emergency Communication System / Body Electronics
Difficulty
Type
Manufacturer
Recommended Tools
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