AutoCodes – Lincoln – B1D78 Lincoln

B1D78 Lincoln Code - Auxiliary Input Circuit Open

Quick Answer

Audio signals are sent from the Audio Input Jack to the Accessory Protocol Interface Module (APIM). Common causes include Faulty Audio Input Jack, Faulty Accessory Protocol Interface Module (APIM), Faulty Audio Control Module (ACM). Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: B1D78 Lincoln indicates Auxiliary Input Circuit Open.
Common causes: Common causes include Faulty Audio Input Jack, Faulty Accessory Protocol Interface Module (APIM), Faulty Audio Control Module (ACM).
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 497

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Sep 01, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B1D78 Lincoln Description

Audio signals are sent from the Audio Input Jack to the Accessory Protocol Interface Module (APIM). The signals are then sent to the ACM. There are no external power or ground circuits to the audio input jack. The Diagnostic Trouble Code (DTC) sets in continuous memory by the navigation ACM (vehicles without the SYNC® system only) when an open is detected in the audio input jack circuitry for greater than 250 milliseconds.

OBDII Code B1D78 Lincoln - Auxiliary Input Circuit Open - AutoCodes.com — B1D78 Lincoln Code - Auxiliary Input Circuit Open

What does this mean?

What are the Possible Causes of the DTC B1D78 Lincoln?

Faulty Audio Input Jack
Faulty Accessory Protocol Interface Module (APIM)
Faulty Audio Control Module (ACM)

How to Fix the DTC B1D78 Lincoln?

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.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B1D78 Lincoln 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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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about B1D78 Lincoln Code

1. What are the common symptoms of OBDII code B1D78 Lincoln - Auxiliary Input Circuit Open?

- The common symptoms include the auxiliary input not working, no sound from connected devices, and the audio system not recognizing external inputs.

2. What can cause the OBDII code B1D78 Lincoln - Auxiliary Input Circuit Open?

- The code can be caused by a loose or disconnected auxiliary input connector, a faulty auxiliary input port, or damaged wiring leading to the input circuit.

3. How can I diagnose the issue related to OBDII code B1D78 Lincoln - Auxiliary Input Circuit Open?

- You can start by visually inspecting the auxiliary input port and its wiring for any visible damage. Using a multimeter to check for continuity in the circuit can help pinpoint the issue.

4. Is it safe to continue driving with the OBDII code B1D78 Lincoln - Auxiliary Input Circuit Open?

- Yes, it is generally safe to continue driving as this code does not affect the vehicle's drivability or safety. However, the auxiliary input functionality will be compromised.

5. Can I repair the OBDII code B1D78 Lincoln - Auxiliary Input Circuit Open myself?

- If you have experience with automotive electrical systems and wiring, you may be able to repair the issue yourself by fixing any loose connections, replacing damaged wiring, or repairing the auxiliary input port.

6. How much does it typically cost to fix the OBDII code B1D78 Lincoln - Auxiliary Input Circuit Open at a repair shop?

- The cost of repairing this code can vary depending on the underlying issue, but it may range from $50 to $200 for parts and labor.

7. Will resetting the OBDII code B1D78 Lincoln - Auxiliary Input Circuit Open make it go away permanently?

- Resetting the code may temporarily clear the error, but if the root cause of the issue is not addressed, the code is likely to reappear once the system detects the problem again.

8. Can a faulty audio system or head unit trigger the OBDII code B1D78 Lincoln - Auxiliary Input Circuit Open?

- While it's possible for a faulty audio system to cause issues with the auxiliary input, the code is primarily related to problems in the input circuit itself rather than the head unit.

9. Are there any common DIY fixes for the OBDII code B1D78 Lincoln - Auxiliary Input Circuit Open?

- DIY fixes may include checking and reconnecting any loose wiring, ensuring a secure connection at the auxiliary input port, and inspecting for any visible damage in the circuit.

10. How long does it typically take to repair the OBDII code B1D78 Lincoln - Auxiliary Input Circuit Open?

- The repair time can vary based on the complexity of the issue and the expertise of the person performing the repair. In general, it may take anywhere from 30 minutes to a few hours to address this code.