Land Rover Forums - Land Rover Enthusiast Forum

Land Rover Forums - Land Rover Enthusiast Forum (https://landroverforums.com/forum/)
-   Discovery II (https://landroverforums.com/forum/discovery-ii-18/)
-   -   Cruise Control Not Working (https://landroverforums.com/forum/discovery-ii-18/cruise-control-not-working-79725/)

Tony C 06-14-2016 07:11 PM

Cruise Control Not Working
 
I haven't been on here in quite some time, which, I suppose, is good in one way - I haven't needed to diagnose a problem in a long time! Anyway, I'm back, and perhaps you all can help me out.
My cruise control is not working. No I haven't checked the fuses, because I don't know which one it's on, and yes, I did replace the module. Other than the fuse, any suggestions? The symptom is that the set switch on the steering wheel has no affect. Nada. Thanks in advance for the help!:disco:

mollusc 06-15-2016 07:21 AM

Does the light come on when you turn on the system? If so, you probably have a vacuum leak in one of the lines. If no light, it's likely a fuse issue. Check the RAVE for the location of fuses.
Could also be the steering wheel switch itself, but that would be less likely than a vacuum leak.

Best4x4 06-15-2016 07:32 AM

On a D2 it could be as easy as a vacuum line. You also need to check your brake switch, and C/C ECU.

NickAdams 06-15-2016 10:39 AM

Is the SES light on? Universally (I believe) cruise control will not work when a check engine light is on.

Best4x4 06-15-2016 05:15 PM

C/C and a SES light shouldn't disable the C/C. It's more than likely a vacuum line issue, brake switch, or C/C ECU.

If that doesn't fix it you could have a wiring issue, blown fuse (other stuff would be INOP though as fuses 25 and 30 power other equipment) as well, bad clock spring on the steering wheel, or an issue with the SLABS or BCU.

Tony C 06-15-2016 10:33 PM


Originally Posted by mollusc (Post 570800)
Does the light come on when you turn on the system? If so, you probably have a vacuum leak in one of the lines. If no light, it's likely a fuse issue. Check the RAVE for the location of fuses.
Could also be the steering wheel switch itself, but that would be less likely than a vacuum leak.

No light; but can't, for the life of me, find the fuse location! RAVE doesn't have it, nowhere I have seen online (google search) has it! Do you know which fuse, and in which fuse box, it is?

Tony C 06-15-2016 10:35 PM


Originally Posted by Best4x4 (Post 570801)
On a D2 it could be as easy as a vacuum line. You also need to check your brake switch, and C/C ECU.

Replaced the CC ECU, vacuum lines look good. Can't locate the fuse, though. Do you know which it is?:bow:

mollusc 06-16-2016 06:56 AM

This is from the D2 electrical library. Plenty of fuses and links identified here...

OPERATION
Cruise Control Supply
Circuit supply
A feed from the battery positive terminal is connected by a R wire to the engine compartment fusebox, where it passes through fuse 16 and fusible link 8.
A feed from fuse 16 passes to the coil of the horn relay. From the coil of the horn relay, the feed is connected to the set/accel and res/suspend switches on a PO wire, via header C0291 LHD/C0286 RHD and the rotary coupler.
A feed from fusible link 8 is connected to the passenger compartment fusebox on a NW wire and from the fusebox to the ignition switch on a N wire.

Ignition switch supply
With the ignition switch in position II, the feed from fusible link 8 flows from the ignition switch to the passenger compartment fusebox on a W wire. The feed continues through fuse 30 in the passenger compartment fusebox and is connected by a GLG wire to the cruise control switch.
With the ignition switch in position II, a second feed from fusible link 8 flows from the ignition switch to the passenger compartment fusebox on a Y wire. The feed continues through fuse 25 in the passenger compartment fusebox and is connected to the brake pedal switch by a GO wire.

Cruise Control Operation
When the cruise control switch is on, the feed from fuse 30 in the passenger compartment fusebox, passes through the cruise control switch contacts to provide power input to the cruise control ECU pin C0239-8 on a WY wire.
Simultaneously, the feed also passes through the cruise control switch indicator lamp which illuminates. The indicator lamp is connected to earth on a black wire via header C0760 to earth header C0017 LHD/C0018 RHD. The cruise control ECU is earthed on a B wire from pin C0239-18, via header C0286 LHD/C0291 RHD to earth header C0018 LHD/C0017 RHD.
When the brake or clutch pedal or is not depressed, the feed from fuse 25 in the passenger compartment fusebox flows to a pair of contacts in the brake pedal switch on a GO wire.


All times are GMT -5. The time now is 11:06 AM.


© 2024 MH Sub I, LLC dba Internet Brands