Bobcat · Cab

Bobcat code M6803: HVAC relay error OFF

What it means

The controller turned the HVAC (heater and air conditioning) relay on but doesn't see its output on, so the cab heater or A/C may not work.

Can I keep running?

OK to run, check it

Yes. It is information or a minor fault: check it when you can, and clear the code once fixed.

Check first

Park on level ground, lower the lift arms and attachment to the ground, stop the engine and remove the key.
Check the fuses and relays for that circuit using the fuse decal or the O&M manual.
Make sure the HVAC relay is fully seated.
Inspect the connector and harness at the part named in the code for corrosion, water, rubbed-through insulation or pushed-back pins.
Restart and try the HVAC again.

Likely causes

Blown HVAC fuse
Failed or loose HVAC relay
Corroded connector or broken wire in the relay circuit

The fix

A fuse, relay or wiring repair usually fixes it. It doesn't stop the loader from working. Call your dealer if the fuse keeps blowing.

Different code on your screen? Snap the display and Mechy reads it.

Questions

What does Bobcat code M6803 mean?

HVAC relay error OFF. The controller turned the HVAC (heater and air conditioning) relay on but doesn't see its output on, so the cab heater or A/C may not work.

Can I keep running with M6803?

Yes. It is information or a minor fault: check it when you can, and clear the code once fixed.

How do I fix Bobcat code M6803?

A fuse, relay or wiring repair usually fixes it. It doesn't stop the loader from working. Call your dealer if the fuse keeps blowing.

Sources

Code meanings vary by model, serial range and software. Confirm with your operator's manual or Bobcat dealer before replacing parts.

Snap the display and Mechy reads the code

Take a photo of the screen and the machine, say what it is doing, and get the checks and the fix as steps with moving drawings.

Use my photo

First guide free. No sign-up, no card.