How to Diagnose and Solve C1860 PRNDL Input #3 Circuit Failure Issues

As a car enthusiast, there’s nothing more satisfying than rolling up your sleeves and getting down to some good old DIY car maintenance. Today, we’re going to tackle a common issue that many car owners face – the C1860 PRNDL Input #3 Circuit Failure.

Understanding the C1860 PRNDL Input #3 Circuit Failure

Before we dive into the solution, let’s first understand what this issue is all about. The C1860 PRNDL Input #3 Circuit Failure is a diagnostic trouble code (DTC) that indicates a problem with the third input circuit of the Park/Reverse/Neutral/Drive/Low (PRNDL) switch. This switch is responsible for indicating the gear position of the automatic transmission to the vehicle’s computer system.

What Causes the C1860 PRNDL Input #3 Circuit Failure?

The C1860 code is typically triggered by a few common issues. These include a faulty PRNDL switch, damaged wiring or connectors, or a malfunctioning transmission control module (TCM).

Diagnosing the C1860 PRNDL Input #3 Circuit Failure

Now that we know what we’re dealing with, let’s move on to diagnosing the problem.

Step 1: Check the PRNDL Switch

The first step in diagnosing this issue is to inspect the PRNDL switch. Look for any signs of damage or wear and tear. If the switch appears to be faulty, it may need to be replaced.

Step 2: Inspect the Wiring and Connectors

Next, check the wiring and connectors that link the PRNDL switch to the TCM. Look for any signs of damage, corrosion, or loose connections. If any issues are found, they will need to be addressed.

Step 3: Test the Transmission Control Module

Finally, you’ll want to test the TCM. This can be a bit more complex and may require the use of a specialized diagnostic tool. If the TCM is found to be faulty, it will need to be replaced.

Solving the C1860 PRNDL Input #3 Circuit Failure

Once you’ve diagnosed the problem, it’s time to solve it.

Step 1: Replace the PRNDL Switch

If the PRNDL switch was found to be faulty during your diagnosis, it will need to be replaced. This is a relatively straightforward process that can be done with basic tools.

Step 2: Repair or Replace Damaged Wiring or Connectors

If any issues were found with the wiring or connectors, these will need to be repaired or replaced. This can be a bit more complex and may require some specialized tools and knowledge.

Step 3: Replace the Transmission Control Module

If the TCM was found to be faulty, it will need to be replaced. This is a more complex process and may require professional assistance.

Conclusion

Dealing with a C1860 PRNDL Input #3 Circuit Failure can be a bit daunting, but with a little knowledge and some elbow grease, it’s a problem that can be solved. Remember, if you’re ever in doubt, don’t hesitate to seek professional help.

FAQs

1. What is a C1860 PRNDL Input #3 Circuit Failure?

This is a diagnostic trouble code that indicates a problem with the third input circuit of the PRNDL switch.

2. What causes a C1860 PRNDL Input #3 Circuit Failure?

This issue is typically caused by a faulty PRNDL switch, damaged wiring or connectors, or a malfunctioning TCM.

3. How can I solve a C1860 PRNDL Input #3 Circuit Failure?

The solution will depend on the cause of the problem. It may involve replacing the PRNDL switch, repairing or replacing damaged wiring or connectors, or replacing the TCM.