P1246 Volkswagen Code – Alternator Load Input Failed High


The P1246 Volkswagen code indicates an alternator load input failure detected by the engine control module (ECM), caused by excessive voltage levels. This fault can lead to battery drainage and critical engine issues, increasing the risk of vehicle shutdown. Symptoms include unstable engine idle, reduced performance, dashboard warning lights, and difficulty starting the engine. Diagnose using an OBD-II scanner, multimeter, and battery tester to assess alternator and battery health thoroughly. Costs vary from $150 to $600, depending on the issue's complexity, with alternator replacement ranging from $200 to $400. Prompt professional evaluation and repair prevent escalation and ensures vehicle safety and reliability. Discover actionable steps and insights to effectively address this code.

P1246 VW Code Meaning

The P1246 code in Volkswagen cars is about a problem with the throttle control system. It often relates to the alternator's load input circuit when the input signal is too high. The Engine Control Module (ECM) needs accurate data from the alternator to help the engine run smoothly. If there is an issue with this data, the engine might not work as well.

This code appears when the ECM gets a voltage that is higher than what it should be. The alternator, which charges the battery and powers the car's electrical system, sends load information to the ECM. If the ECM sees a higher load than expected, it will show the P1246 code. This can happen because of problems with wiring, bad alternator parts, or a faulty ECM.

To fix this, mechanics usually start by checking the alternator's wires and connections for any damage or rust. They use diagnostic tools to compare the alternator's output with what the manufacturer says it should be.

Fixing the P1246 code means finding and solving the underlying problem to keep the car running well.

Error Code P1246 Symptoms

When Volkswagen cars show Error Code P1246, it usually means there's a problem with the throttle control. This can cause a few noticeable issues:

  1. Unsteady Engine Idle: The car might have an uneven engine idle. You might notice the engine's RPMs going up and down when the car is stopped, which can make the engine feel rough and even cause it to stall.
  2. Reduced Performance: The car may not perform as well as usual. It might accelerate slowly, and the engine might not feel as responsive, affecting your driving experience.
  3. Dashboard Warning Lights: The Check Engine Light may come on. Other lights related to the car's electrical system might also appear on the dashboard, signaling the need for a check-up.

Addressing these issues quickly can help keep your vehicle running smoothly and avoid bigger repair costs later.

Causes of VW P1246 Fault Code

Error Code P1246 in Volkswagen cars often points to problems with the throttle control system.

Let's break down the possible reasons:

  1. Throttle Position Sensor (TPS) Problem: The TPS checks where the throttle is and sends this info to the engine's computer. If it's not working right, it might send wrong signals, which can mess up the alternator's readings.
  2. Wiring Troubles: If the wires connecting the alternator and the car's computer are damaged or rusty, the electrical signals can get mixed up. This might make the car think the alternator is working too hard.
  3. Bad Alternator: If the alternator isn't doing its job, it might mess up the voltage. This can cause wrong readings and trigger the P1246 code.

Each of these issues can cause the P1246 code.

To find the problem, check each part to see what's going wrong.

Tools Needed to Diagnose

To figure out what's causing the P1246 error in Volkswagen cars, you need some special tools. These tools help you find problems in the car's electrical system, especially around the alternator.

  1. OBD-II Scanner: This tool connects to the car to check for issues. It shows the error code and gives more details about what's happening. Some scanners show live data, which helps you understand the problem better.
  2. Digital Multimeter: This tool checks the electricity in the alternator. It measures if the voltage, current, and resistance are normal or if something is wrong.
  3. Battery Tester: This tool checks if the battery is working well. Sometimes, a bad battery can look like an alternator problem. The tester checks how the battery charges and how well it powers the car.

How to Fix P1246 VW Error Code – Step by Step

Step 1:

Verify the condition of the alternator, as the P1246 error code indicates a problem with the alternator load input. Inspect the alternator's wiring for any signs of damage or corrosion, ensuring all connections are secure.

Step 2:

Use a multimeter to test the alternator's output voltage. It should typically range between 13.5 and 14.5 volts. Any deviation from these values may suggest a malfunctioning alternator that needs further attention.

Step 3:

Examine the battery's condition and its terminals. A weak or faulty battery can trigger erroneous error codes. Clean the battery terminals to remove any corrosion and ensure a snug fit of the cables.

Step 4:

Consider replacing the battery if it fails to hold a charge or shows signs of wear. A new battery can prevent further issues related to power supply and error codes.

Step 5:

If these steps do not resolve the issue, consider the possibility of a malfunctioning Engine Control Module (ECM). Use professional diagnostic tools to reprogram or replace the ECM, if required, though this should be a last resort.

Follow these steps diligently to efficiently and effectively resolve the P1246 code.

Common Diagnosis Mistakes

After dealing with the P1246 VW error code, there are common mistakes that people often make. These can get in the way of fixing the problem. Here are some things to watch out for:

  1. Replacing Parts Without Checking: Sometimes, people change the alternator or battery right away. They might think these parts are broken, but they should test them first. This can save money and time.
  2. Not Checking Wires: The problem might be with the wires, not the parts. If the wires are damaged or rusty, it can cause issues. So, it's good to check the wiring and connectors carefully.
  3. Missing Software Updates: The error might be due to old software in the car's control unit. Updating the software could fix the problem without needing to change any hardware. Always check for the latest software updates.

Avoiding these mistakes can make the diagnostic process smoother and more effective.

P1246 VW Repair Cost

Fixing the P1246 error in a Volkswagen can cost between $150 and $600, depending on what's wrong. The cost can vary based on the car model, how bad the alternator problem is, and labor fees at the shop.

If you need a new alternator, expect to pay $200 to $400 for the part. Labor might add another $100 to $200.

If the problem is with the wiring or a bad sensor, repairs might be cheaper, around $150 to $300.

Choosing between original and aftermarket parts can change the cost too. Original parts usually cost more but may fit better and last longer. An original alternator should perform like the one your car came with, while aftermarket parts might be cheaper but not last as long.

To manage costs, get quotes from different repair shops. This way, you can find the best price and service for fixing your car.

Related Error Codes on Volkswagen

Volkswagen cars can show different error codes when something isn't working right. These codes help find out what the problem is. For example, the P1246 code is about the alternator not working correctly. Other codes can mean different problems with the car's electrical system.

Here's a simple list of some common error codes and what they mean:

  • P0562: The car's voltage is too low.
  • P0563: The car's voltage is too high.
  • P0622: There's a problem with the alternator's control circuit.
  • P2503: The charging system has low voltage.

Each code can show different symptoms and have different causes. For instance, if you see the P0562 code, it might mean the battery is weak or some connections are loose.

On the other hand, P0563 could mean the voltage regulator is not working. If you get a P0622 code, the alternator's control circuit might have issues. P2503 usually means there's a voltage drop problem.

It's important to use the right tools to find where these errors are coming from. A Volkswagen expert can help understand and fix these codes.

Can I drive safely with P1246 VW?

No, you shouldn't drive with the P1246 code on your VW.

It means your alternator isn't working right, which can make your car's battery die. This could cause your car to stop suddenly.

It's best to see a mechanic soon to fix it.

People Also Ask

How Often Do Alternator Load Input Failures Occur in Volkswagens?

Alternator load input failures in Volkswagens don't happen very often, but it's good to get regular check-ups to prevent problems. For the best information, ask a Volkswagen service center about how often this issue comes up.

What Models of Volkswagen Are Most Affected by the P1246 Code?

Some Volkswagen models, like the Jetta, Passat, and Golf, have shown more issues with the P1246 code. This code often relates to alternator problems. It's important to check these models regularly and fix any issues to keep them running well.

Can Regular Maintenance Prevent the P1246 VW Error Code?

Regular maintenance can help stop some error codes from happening. By checking things like the alternator and battery often and replacing them if needed, you can avoid problems with the car's electrical system that might cause error codes like P1246.

Does the P1246 Code Affect Fuel Efficiency in Volkswagen Vehicles?

The P1246 code in a Volkswagen can make the car use more fuel. This happens because the engine control module might not handle the alternator correctly, which can lead to problems with the car's electrical system and battery charging.

Are There Any Recalls Related to the P1246 VW Error Code?

There are no recalls from Volkswagen for the P1246 error code. It's best to check with your local dealer for any updates or advice. They can tell you if there are any service bulletins or advisories related to this issue.

Recent Posts