AutoCodes – Toyota – U1117 Toyota

U1117 Toyota Code - Lost Communication with Accessory Gateway

Quick Answer

The Controller Area Network (CAN) is a standard bus system in vehicles that enables the connection of automotive devices without the need for a host computer. Common causes include Faulty Controller Area Network (CAN) Communication System, Faulty Multiplex Network Door ECU, Multiplex Network Door ECU harness is open or shorted. 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: U1117 Toyota indicates Lost Communication with Accessory Gateway.
Common causes: Common causes include Faulty Controller Area Network (CAN) Communication System, Faulty Multiplex Network Door ECU, Multiplex Network Door ECU harness is open or shorted.
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 8,831

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 Mar 28, 2023

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code U1117 Toyota Description

The Controller Area Network (CAN) is a standard bus system in vehicles that enables the connection of automotive devices without the need for a host computer. The exchange of operating information and commands among devices is facilitated by pre-programmed information about the required message exchange on the serial data circuits. Communication is carried out using two dedicated wires, known as CAN high and CAN low, with both lines carrying 2.5V when the CAN bus is in idle mode. During the transmission of data bits, the CAN high line increases to 3.75V while the CAN low drops to 1.25V, creating a 2.5V differential between the lines. Since communication relies on a voltage differential between the two bus lines, the CAN bus is NOT sensitive to inductive spikes, electrical fields, or other noise. The Diagnostic Trouble Code (DTC) sets when a periodic message from the Multiplex Network Door ECU has not been received.

OBDII Code U1117 Toyota - Lost Communication with Accessory Gateway - AutoCodes.com — U1117 Toyota Code - Lost Communication with Accessory Gateway

What does this mean?

What are the Possible Causes of the DTC U1117 Toyota?

Faulty Controller Area Network (CAN) Communication System
Faulty Multiplex Network Door ECU
Multiplex Network Door ECU harness is open or shorted
Multiplex Network Door ECU circuit poor electrical connection

How to Fix the DTC U1117 Toyota?

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 does this mean?

Code Tech Notes

When there are problems with the way different systems in a vehicle communicate with each other using a technology called Controller Area Network (CAN) communication, Diagnostic Trouble Codes (DTC) are displayed. These codes can be caused by issues with the main bus or branch of the communication network, or with the Electronic Control Units (ECUs) and sensors that make up the different systems. If you see code for both the CAN communication problems and internal or power source problems at the same time, you should focus on fixing the internal or power source problems first.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the U1117 Toyota 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 Toyota Models

U1117 2013 Toyota RAV4 — Lost Communication with Accessory Gateway
U1117 2014 Toyota RAV4 — Lost Communication with Accessory Gateway
U1117 2015 Toyota RAV4 — Lost Communication with Accessory Gateway
U1117 2016 Toyota RAV4 — Lost Communication with Accessory Gateway
U1117 2017 Toyota RAV4 — Lost Communication with Accessory Gateway
U1117 2018 Toyota RAV4 — Lost Communication with Accessory Gateway

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 U1117 Toyota Code

1. What does the OBDII code U1117 mean on a Toyota?

U1117 indicates a loss of communication with the Accessory Gateway Module, which acts as a bridge for communication between various onboard systems.

2. What are the common symptoms of code U1117 on a Toyota?

Symptoms can include malfunctioning accessories, such as power windows or mirrors, abnormal dashboard warnings, or intermittent electronic issues.

3. What causes code U1117 to appear on a Toyota?

Common causes include a faulty Accessory Gateway Module, wiring or connection issues, a blown fuse, or a failing CAN bus network.

4. Can a weak battery trigger code U1117 on a Toyota?

Yes, a weak or failing battery can cause communication errors like U1117 by destabilizing the vehicle's electrical system.

5. How do you diagnose a U1117 code on a Toyota?

Diagnosis involves checking for wiring or connector damage, inspecting the Accessory Gateway Module, verifying power and ground signals, and ensuring proper communication on the CAN bus.

6. Is it safe to drive with a U1117 code on a Toyota?

While the vehicle may still be drivable, unresolved communication issues can lead to malfunctioning accessories or additional system errors over time.

7. How can you fix code U1117 on a Toyota?

Repairs may include reconnecting or replacing damaged wires, repairing connectors, replacing a faulty Accessory Gateway Module, or resetting the system.

8. Can an aftermarket accessory cause code U1117 on a Toyota?

Yes, improperly installed aftermarket accessories can disrupt the communication network and trigger this code.

9. Do you need to reprogram the Accessory Gateway Module if it's replaced?

In some cases, reprogramming or initialization may be required after replacing the module to ensure proper communication.

10. How much does it typically cost to fix code U1117 on a Toyota?

Costs vary depending on the root cause, but repairs could range from $100 for simple wiring fixes to $500 or more for module replacement and programming.