B108C Code - Start Button Circuit 'B'
Quick Answer
Conventional Ignition Switch: The ignition switch is a multiple position rotary switch that is controlled by a lock cylinder and a key. Common causes include Faulty Start Button Switch, Start Button Switch harness is open or shorted, Start Button Switch circuit poor electrical connection. Severity is Moderate - service should be scheduled soon. The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
- What it means
- B108C indicates Start Button Circuit 'B'.
- Common causes
- Common causes include Faulty Start Button Switch, Start Button Switch harness is open or shorted, Start Button Switch circuit poor electrical connection.
- Severity
- Moderate - service should be scheduled soon.
- Can I drive?
- The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
Code B108C Description
The ignition switch is a multiple position rotary switch that is controlled by a lock cylinder and a key. The ignition switch provides voltage to the ACC, ON, or START-designated circuits depending on the position it is placed. The Body Control Module (BCM) calculates the positions based on the voltage received from the ACC and ON-designated circuits.
The key removal inhibit solenoid (also known as the key release interlock actuator) is an electronically controlled solenoid that prevents the ignition lock cylinder from being turned to the OFF position unless the gear selector lever is in the PARK position. The key removal inhibit solenoid is part of the ignition switch.
Push Button Ignition Switch:
The push button ignition switch is used instead of a conventional ignition switch to achieve the various ignition modes. The push button ignition switch is a momentary dual contact switch. Both sets of contacts are normally open and receive the voltage at all times. When the START/STOP button is pressed, the voltage is sent to the BCM, the RFA module, and the PCM to indicate a button press.
The ignition switch has a LED for switch illumination when the backlighting is activated.
What are the Possible Causes of the DTC B108C?
- Faulty Start Button Switch
- Start Button Switch harness is open or shorted
- Start Button Switch circuit poor electrical connection
- Faulty Body Control Module (BCM)
How to Fix the DTC B108C?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
B108C:24 Start Button Circuit 'B' Signal Stuck High
B108C:2F Start Button Circuit 'B' Signal Erratic
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the B108C code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Information for Specific Makes
- B108C Ford — Start Button Circuit 'B'
- B108C Lincoln — Start Button Circuit 'B'
- B108C Mercury — Start Button Circuit 'B'
Frequently Asked Questions about B108C Code
1. What are the common symptoms of OBDII code B108C (Start Button Circuit 'B')?
Common symptoms include the inability to start the vehicle using the push-button start, intermittent starting issues, and the engine stalling unexpectedly.
2. What are the possible causes of OBDII code B108C?
Possible causes of this code include a faulty start button switch, a wiring issue in the start button circuit, a malfunctioning ignition switch, or a problem with the vehicle's electronic control module.
3. How can I diagnose the cause of OBDII code B108C?
Diagnosing the cause of this code typically involves using a scan tool to retrieve the code, checking the wiring and connections in the start button circuit, testing the start button switch for proper operation, and inspecting the ignition switch for any faults.
4. Can I drive my vehicle with OBDII code B108C?
It is not recommended to drive your vehicle with this code present, as it can lead to starting issues or unexpected stalling, which can be dangerous. It is best to address the issue promptly.
5. How can I repair OBDII code B108C?
Repairing this code may involve replacing the faulty start button switch, repairing any damaged wiring in the circuit, replacing the ignition switch if necessary, or reprogramming the electronic control module.
6. Will OBDII code B108C cause permanent damage to my vehicle?
While the code itself may not cause permanent damage, ignoring the underlying issue can lead to further complications with the vehicle's starting system, potentially resulting in more severe damage over time.
7. Can I reset OBDII code B108C on my own?
You can attempt to clear the code using an OBDII scanner, but it is important to first diagnose and address the root cause of the code to prevent it from reoccurring.
8. How much does it cost to repair OBDII code B108C?
The cost of repairing this code can vary depending on the specific cause of the issue, the parts needed for repair, and the labor rates of the mechanic or dealership. It is recommended to obtain quotes from different sources for an accurate estimate.
9. Is OBDII code B108C a common issue in certain vehicle makes and models?
This code can be more common in vehicles equipped with push-button start systems, particularly in certain makes and models known for issues with their starting systems. Conducting research specific to your vehicle can provide more insight.
10. Can a DIY enthusiast repair OBDII code B108C?
Depending on your level of automotive expertise and access to tools, some DIY enthusiasts may be able to diagnose and repair this code themselves. However, it is important to have the necessary knowledge and skills to work on the vehicle's starting system safely and effectively.
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