Cruise control non-functional

[Pystri]

Just bought a 2004 E85 3.0i manual. I'm loving it in every way except one: the cruise control doesn't work. I'm fairly certain that this isn't user error: I'm pushing the stalk away from me while going above 20mph (usually much above), and afaik that's all that should be required to activate the system. Looking at a decode of the VIN it does appear that CC was originally specced, so this should be the factory install.

I've hooked up an OBD scanner, and there is an error code related to cruise control being logged, but it's not immediately clear what it means:

2806 DME: Cruise control: time limit of data transmission reached

So far I've:

• Checked the fuse

• Replaced the clutch pedal sensor

If anyone could offer any advice, my right foot would be immensely grateful.

[Scooba_Steve]

Checked the fuse

Which fuse?
Are your brake lights constantly on?

Not seen that code before but it sounds like a no comms issue. So continuity to the DME box in the engine bay would be worth checking.

[Pystri]

Which fuse?

Apologies - the fuse for the cruise control. Number 28 I think? Brake lights are functioning correctly.

Continuity of the wires from the stalk do you mean?

Appreciate the help!

[Scooba_Steve]

Apologies - the fuse for the cruise control. Number 28 I think? Brake lights are functioning correctly.

No need, when I had an issue fuse 45 was blown so it might be worth checking them all. Though my brake lights were constantly on.

Continuity of the wires from the stalk do you mean?

That's one part of it. I *think* that the stalk will go to the LCZ (or somewhere else) for power with one wire into the engine DME.
I don't think you can check the continuity of the stalk positions but it might be worth a try, unless you can swap with someone who has a known working stalk.

Sadly elec issues are usually a massive paint to isolate.

[BumpyZ4]

It should be fairly easy to check the wires as there are only three wires (GROUND, POWER & COMMUNICATION).

[Usel]

As BumpyZ4 says check at the plug with a multimeter that you have 12v on the ground and power wire with the engine running (car stationary.)

As Scooba_Steve says you can't check the inputs from the cruise control stalk without actually taking the casing off. If you do take it apart be careful as the ribbon for the button for resume is connected to both halves of the casing and needs disconnecting before the casing comes fully off.

I've had that error code before and it didn't stop the cruise control working on my car. There isn't much information about that fault on the Internet unfortunately. Even read a case about an E46 having the error code and they didn't even have cruise on the car.

[Pystri]

Wow what a helpful forum! Thanks everyone for your advice. I'll try everything suggested and report back.

[Scooba_Steve]

Wow what a helpful forum!

Yeah it's defo the best one, all the others have significantly less knowledge and the FB ones are a nightmare

[brillomaster]

this might be obvious, but only trying to help... if i remember correctly, you have to turn the system on with the button at the end of the stalk (green light comes on) and then set the cruise control speed by pushing the stalk away from you... apologies if this is already what you're doing...

[Usel]

this might be obvious, but only trying to help... if i remember correctly, you have to turn the system on with the button at the end of the stalk (green light comes on) and then set the cruise control speed by pushing the stalk away from you... apologies if this is already what you're doing...

You don't need to do that, there's no green light.

All you need to do is be above 20mph? and press the stalk forward to set the cruise speed. The off part on the stalk in reality is cancel. There is no real 'off.'

[Pystri]

Good news everyone: I have cruise control

I popped off the steering column cowl with the intent of checking the signals from the stalk, and wouldn't you know it, it wasn't even plugged in! I probably should have checked that first...

Interestingly it wouldn't work when I put the old clutch pedal switch back in, so I guess that had also coincidentally failed.

Thanks again to everyone who offered advice.

[Usel]

Great!

Seems like someone tried to fault find and gave up

[BumpyZ4]