Cruise control not working

[cgtmiles]

Help!

I noticed today that the cruise control (std not ACC) is not working anymore! I hardwired in a dashcam last week so I must have done something to stop it working but I can’t work out what. I have control on the steering wheel buttons and these work as I use them for my ghost code. The brake lights are working and the gear select indicator is working so I assume it’s nothing to do with missing signals from the pedals (if that’s how it works) and the fuse (top middle 5A) is ok. I connected Carista and there was only an error linked to the ghost on there.

I’m assuming that maybe I’ve somehow knocked a connector under the steering wheel but I can’t find any info on a cruise control module or it’s location and I can’t see anything obviously wrong. I’ve looked through the resources on here and again I can’t see any references to a CC module. Can anyone advise on the location of any connected modules or generally where I should go next with faultfinding as I am past my limit of understanding?

many thx in advance
Chris

 

[Spaghetti]

Worth checking the clutch pedal switch.

I assume also that you’ve tried disconnecting the battery aswell?

 

[Niknak]

Any other faults like hill start assist

 

[Deaky]

Also check you haven't dislodged a fuse

T6 - Fuse Card | VW T6 Transporter Forum (t6forum.com)

 

[Niknak]

Side not btw but just cause brake lights are working does not mean the switch is ok, the red and black from the switch goes to the abs, ecu, and bcm and has a climbing voltage when pressed the other wire is a decreasing voltage that’s for the lights

 

[cgtmiles]

Also check you haven't dislodged a fuse

T6 - Fuse Card | VW T6 Transporter Forum (t6forum.com)

I have had a general look and nothing is obviously wrong and I’ve checked the fuse that I believe is the CC fuse on a PV and all looks ok.

 

[cgtmiles]

Any other faults like hill start assist

I can’t see any error codes and I haven’t noticed anything else wrong. I had a play with stuff while parked up and everything seems to be operating. I haven’t specifically checked the hill assist although I know it is still checked on the display

 

[cgtmiles]

Worth checking the clutch pedal switch.

I assume also that you’ve tried disconnecting the battery aswell?

I actually haven’t disconnected the battery. Do you think this would help though as I’m not getting any error codes etc to clear? I believe there is a procedure to reset stuff so I guess you mean that I should follow that as opposed simply disconnecting (not sure what’s the difference)

 

[cgtmiles]

Regarding checking the pedal switches, I had a look before and I couldn’t really see anything. Is there any advise for what I should be looking at or for? (I’m not great at this sort of thing)

 

[Ads_Essex]

You definitely haven’t switched it off on the stalk, I take it? Easily done..

 

[cgtmiles]

Err, the control is in the steering wheel buttons so I don’t think I think a stalk for CC.

part of me hopes not but it would be great if that wasthe issue

 

[cgtmiles]

You definitely haven’t switched it off on the stalk, I take it? Easily done..

I didn’t have much of a chance to look into this issue over the weekend and have only just checked to see if I have a stalk as well as the MFSW buttons, I don’t

It would have been embarrassing but I was beginning to hope this was the issue. My wife is going to work tomorrow so I will have some room to look at the pedals. Looks like the brake switch is located by the brake server so it’s just the clutch pedal to check. Is there anything else anyone can recommend me checking?

 

[The Bear78]

Going out on a limb as I do not know exactly how the systems work but do you still need to press the clutch to start the engine and do you still see the current gear on the MFD?

 

[cgtmiles]

Yeah, I’ve tested it and it won’t start without the clutch down and the gear selector shows the gear until I press the pedal so it appears like the switch is working fine but I have nothing else to try.
Any ideas?

 

[The Bear78]

Sorry, I've just re-read your first post and saw that you mentioned the gear selector.
I'm a stalk user too so it's a bit difficult to visualise what else there is to try....

 

[cgtmiles]

No worries, thanks anyway.

 

[JasonW]

Came across this on a VW site.... maybe its some help or will point towards the problem from process of elimination...

Cruise Control Issues
Cannot Engage the Cruise Control

Your Volkswagen cruise control will not work if you have any of the following conditions:

• Your vehicle speed sensor is not working. If this is the case, your speedometer will not be working either.
• Your throttle position and engine speed do not match the input position.
• You do not have enough volts going to the PCM or other parts of the system.
• You are in PARK, REVERSE, LOW or NEUTRAL gear.
• Your clutch pedal is depressed/disengaged.
• You are driving less than 30 miles per hour.
• Your traction control system or ABS has been engaged for more than a couple seconds. This can vary.
• Your vehicle speed is too high. Some systems will not operate over 90 m.p.h. for safety reasons.
• You have your foot on the brake pedal.
• Your VW’s system detected an error and gave you a code. This can keep the system from working until you read the code and make repairs.

Common Cruise Control Faults

Fuse – Check your owner’s manual to see where the fuse is located and check the fuse. Replace it with the proper fuse. If the new fuse blows as soon as you engage the cruise control system, you could have an electrical short. Use the wiring diagram and an ohmmeter/voltmeter to find the short.

Brake Pedal Switch – Put your foot on the brakes and make sure they work. If you have no brake lights, you may have a switch problem. The same is true for the parking brake. Since the cruise control is tied into the brake system, if it reads that the brakes are on, it will not engage.

Vehicle Speed Sensor (VSS) – If the VSS is bad, it cannot give accurate speed readings. This will affect the cruise control and the speedometer. If the speedometer is reading accurately, then the VSS is probably not the problem.

Cruise Control Switch – The switch is either on the steering wheel or on the column. If some of the buttons work, but others do not, it is probably a bad switch. If none of your buttons work, there could be a short in the wiring between the switch and the PCM. You can check this by removing the steering wheel. Before you do that, make sure you deactivate the air bag system by removing the fuse and waiting at least 15 minutes.

Cruise Control Module or PCM – You may see a Check Engine Light when you have a faulty module or PCM. It will trigger a code that will help you determine where the problem is at in the system. If the module is the problem, check the ground and the power connections. If there is no problem there, you need to replace the module.

Vacuum Actuator – The diaphragm on the inside of the actuator can become damaged or there may be a leak in the vacuum system. It could be a bad control solenoid that is keeping the actuator from working properly. You will need to replace the unit.

Throttle Actuator – If your VW has an electronic throttle control, you may have a bad motor in the actuator. If it is not opening and closing the throttle, your engine is probably not running above an idle. You will also see the Check Engine Light, and there will be codes that indicate the throttle actuator motor or control system have problems.

 

[cgtmiles]

I found this but I’m pretty sure all the conditions are ok (or at least they are when driving whenever I’m allowed to travel anywhere again) and I can’t believe that all of the faults listed would not show as errors. If there is a cruise control module (I haven’t found it yet) then maybe a power issue or a fault would cause it to not be visible to the BCM and so not show an error maybe?

 

[Niknak]

Have you read with vcds ? Did you say that you had taken the feed from the obd socket for dash cam

 

[cgtmiles]

I’ve checked it for errors with Carista and the only error is listed as being caused by the ghost. The ignition feed for the dashcam is taken from a piggy back fuse connected just below the cruise control fuse (I can’t recall what the borrowed fuse was for but the one above is the CC). My thinking was that I’d knocked something while feeding the wire across above the pedals but I really can’t see what I could have done. The permanent live goes down the B pillar to the leisure battery so that can’t be the issue surely.