The OBDII code P1613 can be a source of frustration for Eurovan owners. This diagnostic trouble code, often described as “MIL call up open/short to B+,” signals a communication issue within your vehicle’s engine management system. While the description might sound technical, understanding the basics and potential fixes can empower you to address this problem effectively. This article will break down the P1613 code in the context of Eurovans, explore its possible causes, and guide you through potential solutions.
Understanding the P1613 Code in Your Eurovan
OBDII (On-Board Diagnostics II) codes are standardized codes used across the automotive industry to pinpoint potential problems within a vehicle’s systems. Code P1613 is manufacturer-specific, and in the realm of Eurovans (and other Volkswagen/Audi vehicles), it often points towards an issue in the communication between the Engine Control Module (ECM) and potentially the Transmission Control Module (TCM), although the original forum post suggests it might not always directly involve the TCM. The “MIL call up open/short to B+” part of the description indicates a problem with the signal circuit – it might be open (broken) or shorted to the positive battery voltage (B+). Essentially, the ECM is detecting an unexpected electrical signal or lack thereof on a circuit it uses for communication, triggering the Malfunction Indicator Lamp (MIL), commonly known as the “check engine light.”
Potential Causes of the P1613 Error
Several factors can lead to the P1613 code appearing in your Eurovan. Based on expert insights and community experiences, here are some of the most common culprits:
1. Incorrect ECM Transmission Coding
One of the most intriguing, yet potentially simple, solutions suggested by experienced users revolves around the ECM’s transmission coding. In some cases, particularly after an ECM replacement or reprogramming, the ECM might be incorrectly configured for an automatic transmission when the vehicle actually has a manual transmission, or vice versa. This mismatch can disrupt the expected communication signals and trigger the P1613 code.
The original forum post highlights a direct fix related to this: using VAG-COM (VCDS) software to change the transmission coding within the ECM. The suggestion is to switch the coding from “automatic” to “manual” (code 00001 to 00000 for specific ECU types mentioned in the original post). This implies that in some scenarios, the P1613 error might be a software configuration issue rather than a hardware fault.
2. Transmission Control Module (TCM) Issues
While the “MIL call up open/short to B+” description doesn’t explicitly scream “TCM problem,” issues with the TCM or its interaction with the ECM can indirectly lead to a P1613 code. A faulty TCM, or even the wrong TCM module being installed (as suggested in the original forum post), could disrupt the communication pathways and result in the error. If the TCM is sending incorrect or no signals to the ECM, or if there’s a compatibility issue, a communication error like P1613 can arise.
3. Wiring and Circuit Problems
The “open/short to B+” part of the code description strongly points towards electrical wiring problems. Issues in the wiring harness connecting the ECM and TCM (or related modules) are prime suspects. These problems can include:
- Short circuits: A wire’s insulation might be damaged, causing it to touch metal or another wire, leading to an unintended electrical path to ground or B+.
- Open circuits: A wire might be broken or corroded, interrupting the electrical circuit and signal flow.
- Connector issues: Connectors at the ECM, TCM, or along the wiring harness can become corroded, loose, or damaged, causing poor electrical contact.
These wiring faults can directly affect the communication signals between modules, leading the ECM to register the P1613 error.
Troubleshooting and Solutions for P1613
Addressing the P1613 code requires a systematic approach. Here’s a step-by-step guide incorporating the insights from the original forum post and general automotive diagnostic best practices:
1. ECM Transmission Coding Verification and Recoding (VAG-COM/VCDS)
If you have access to VAG-COM (VCDS) or a similar diagnostic tool capable of advanced VW/Audi diagnostics and coding, this should be your first step, especially if you suspect recent ECM work or are unsure of the current coding.
- Connect your VAG-COM/VCDS tool.
- Navigate to the ECM module (Engine Control Module).
- Check the current transmission coding. Compare it to the correct coding for your Eurovan’s transmission type (manual or automatic). The original forum post provides example codes, but always verify against reliable sources specific to your Eurovan model and year.
- If incorrect, perform recoding. Follow the procedure outlined in the original forum post (or VCDS documentation), which involves logging in with code 01283 and then recoding module 07 with the correct software coding (e.g., changing from 00001 to 00000 for manual transmission if currently set for automatic and applicable to your ECU type).
- Cycle the ignition. As noted in the original post, the new coding may not take effect until the ignition is cycled (turned off and then back on).
- Clear the P1613 code using your diagnostic tool and re-scan to see if it returns.
Caution: Incorrect ECM coding can have unintended consequences. Proceed with caution and ensure you understand the VAG-COM/VCDS software and coding process before making changes. Consult reliable resources and, if unsure, seek professional assistance.
2. TCM Module Inspection
If recoding doesn’t resolve the P1613 code, or if you suspect a TCM issue, inspect the TCM module:
- Locate the TCM. Its location varies depending on the Eurovan model and year, but it’s often found under the dashboard or seats. Consult your Eurovan repair manual for the exact location.
- Visually inspect the TCM. Look for any signs of damage, corrosion, or loose connectors.
- Verify TCM part number. Ensure the installed TCM is the correct part number for your Eurovan’s year, model, and transmission type. An incorrectly matched TCM can cause communication problems.
3. Wiring Harness and Circuit Examination
Thoroughly inspect the wiring and circuits related to the ECM and TCM. A Bentley manual, as recommended in the original forum post, is invaluable for this step, providing detailed wiring diagrams for your Eurovan.
- Visual inspection: Carefully examine the wiring harness for any signs of damage, chafing, cuts, or melted insulation. Pay close attention to areas where the harness might rub against metal parts or sharp edges.
- Connector inspection: Inspect all connectors at the ECM, TCM, and along the wiring path. Look for corrosion, bent pins, or loose connections. Clean and reseat connectors as needed.
- Continuity and voltage testing: Use a multimeter to perform continuity tests on individual wires to check for open circuits and voltage tests to check for shorts to ground or B+. Refer to wiring diagrams in your Bentley manual to identify the specific circuits to test.
4. Professional Diagnosis
If you are not comfortable with electrical diagnostics or if the above steps do not resolve the P1613 code, it’s best to seek professional help from a qualified automotive technician experienced with Eurovans and Volkswagen/Audi vehicles. They will have access to advanced diagnostic tools and expertise to pinpoint the root cause of the problem and perform necessary repairs.
The Value of Diagnostic Tools and Resources
As highlighted in the original forum discussion, having the right tools and resources is crucial for effectively diagnosing and resolving automotive issues like the P1613 code.
- VAG-COM/VCDS (or equivalent): For VW/Audi vehicles, VAG-COM (VCDS) is an indispensable tool for reading codes, performing advanced diagnostics, and coding modules like the ECM.
- OBDII Scanner: A basic OBDII scanner is essential for reading and clearing diagnostic trouble codes, providing a starting point for troubleshooting.
- Bentley Repair Manual: A Bentley manual specific to your Eurovan model is a comprehensive resource containing wiring diagrams, repair procedures, and detailed information that is invaluable for DIY repairs and diagnostics.
- Multimeter: A multimeter is necessary for electrical circuit testing to identify shorts, opens, and voltage issues.
Online forums and communities, like the one where the original post originated, can also be valuable resources for sharing experiences and solutions. However, always verify information from online sources with reliable repair manuals and professional guidance when needed.
Conclusion
The Eurovan Obdii Code P1613, while initially perplexing, can be systematically diagnosed and resolved. By understanding the potential causes—ranging from ECM coding errors to wiring faults—and following a structured troubleshooting process, you can effectively address this issue. Whether it’s a simple recoding fix or a more involved wiring repair, taking a methodical approach, utilizing the right tools, and leveraging available resources will help you get your Eurovan back on the road and running smoothly.
