If your Tesla Model 3 or Model Y is showing a “D/C Charging Unavailable” message, or you’ve spotted an error in Service Mode like “inletHarnessIrrational”, you’re not alone – and more importantly, we can fix it.

What’s the “D/C Charging Unavailable” Issue?

A leading cause of DC fast charging failure on the Tesla Model 3 and Model Y is a fault with the W Harness – a vital component of the charging system. This issue commonly triggers an internal service alert, such as:

CP_a100_inletHarnessIdIrrational

In Service Mode, this error may include messages like:

“The charge port ECU detects unexpected voltage at the inlet harness identifier pins or is unable to identify the type of inlet harness.”

The Solution: W Harness Repair

At Cleevely EV Mobile, we now offer a dedicated W Harness Repair service for both Model 3 and Model Y vehicles. Our expert technicians are all IMI-certified in high voltage systems, so your Tesla is in the safest possible hands.

We’ve seen this problem many times and have developed a fast, effective repair method to restore full charging capability.

How to Check for the source of the “D/C Charging Unavailable” Issue

  1. Access Service Mode on your Tesla (watch our quick how-to video here).
  2. Look for alerts like “inletHarnessIdIrrational” or messages such as “D/C Charging Unavailable.”
  3. Take a clear photo of the screen showing the alert.

Book Your W Harness Repair

When booking your appointment, please request the “W Harness Repair” and upload a photo of the error screen in Service Mode. This helps us verify the issue and get you booked in without delay.

📩 Submit your booking and upload your photo here:
👉 cleevelymobile.co.uk/contact


Why Cleevely EV Mobile?

Specialist repair for a known Tesla Model 3 & Y charging fault
Fast, mobile service – we come to you
Experienced, IMI-trained EV technicians
Proven fix for D/C charging failure
Mobile service – we come to you
Trusted UK EV experts