AutoCodes – Ford – B1D78 Ford

B1D78 Ford 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 Ford 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 1,127

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 Ford 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 Ford - Auxiliary Input Circuit Open - AutoCodes.com — B1D78 Ford Code - Auxiliary Input Circuit Open

What does this mean?

What are the Possible Causes of the DTC B1D78 Ford?

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

How to Fix the DTC B1D78 Ford?

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 Ford 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 Ford Code

1. What are the common symptoms of OBDII code B1D78 Ford (Auxiliary Input Circuit Open)?

- Common symptoms include the auxiliary input not working, no sound from the connected device, or error messages on the multimedia system.

2. What can cause the OBDII code B1D78 Ford to trigger (Auxiliary Input Circuit Open)?

- The code can be triggered by a loose or disconnected auxiliary input connector, damaged wiring, or a faulty auxiliary input module.

3. How can I diagnose the OBDII code B1D78 Ford (Auxiliary Input Circuit Open)?

- You can diagnose the code by visually inspecting the auxiliary input connection, checking for loose or damaged wiring, and using a multimeter to test for continuity.

4. Can a blown fuse cause the OBDII code B1D78 Ford (Auxiliary Input Circuit Open)?

- Yes, a blown fuse related to the auxiliary input circuit can also trigger the B1D78 code.

5. What is the typical repair for OBDII code B1D78 Ford (Auxiliary Input Circuit Open)?

- The typical repair involves reconnecting or repairing the auxiliary input wiring, replacing a faulty auxiliary input module, or replacing a blown fuse.

6. Are there any DIY tips for fixing the OBDII code B1D78 Ford (Auxiliary Input Circuit Open)?

- DIY tips include checking and securing the auxiliary input connection, inspecting wiring for damage, and replacing blown fuses if necessary.

7. Is it safe to continue driving with the OBDII code B1D78 Ford (Auxiliary Input Circuit Open) present?

- It is generally safe to continue driving with this code, but you may lose the functionality of the auxiliary input until the issue is resolved.

8. Can the OBDII code B1D78 Ford (Auxiliary Input Circuit Open) be intermittent?

- Yes, the issue causing the code can be intermittent, leading to sporadic loss of auxiliary input functionality.

9. Will resetting the OBDII code B1D78 Ford (Auxiliary Input Circuit Open) make it go away permanently?

- Resetting the code may temporarily clear it, but if the underlying issue is not resolved, the code is likely to return.

10. How much does it typically cost to repair the OBDII code B1D78 Ford (Auxiliary Input Circuit Open)?

- The cost of repair can vary depending on the specific cause, but it may range from a simple DIY fix to a more involved repair by a professional, potentially costing anywhere from $50 to $300 or more.