Member Since: 01 Jan 2014
Location: Dumfries, Scotland
Posts: 84
Cruise Control Guru Needed !!!!!
As title
Have had problems with this off and on over the last year, found broken wire in steering wheel loom and replaced, been Ok for last month. I now have no cruise at all now, thought this would be easy to find but not so.
I have checked the new loom Ok.
Have fitted second hand switches that I had still the same.
No fault codes stored.
Removed battery and plugs removed from the engine ECU, checked continuity from plug that goes into cruise control switch right back to engine ECU all OK. Checked with buzzer and bulb.
Cruise control works on resistive ladder so measured resistance between the two wires at the ECU with switches connected and got 5 different resistances. Removed switches and fitted my other switches and got the same results.
I am now thinking switches and wiring back to Engine ECU are all OK.
Replaced Brake light switch because I had one, still not working.
My car being a manual has a clutch switch, quick test it looks like it is a variable resistance but don't know what I should be getting, any body got any ideas. Cant find much info about it. Have calibrated the clutch pedal and it never came back saying readings were out of spec. Doesn't have drive away handbrake release.
Anybody any ideas. What else stops cruise from working?
Engine ECU on way out ? When battery reconnected battery light was on when started and took several minutes at 3000 rpm to go out but looks ok now. 15.2 volts running with lights and heated window on. Goes off as soon as started now. New alternator in august.
No other faults.
22nd Nov 2014 9:09 pm
Robbie
Member Since: 05 Feb 2006
Location: ¯\_(ツ)_/¯
Posts: 17932
Comprehensive checking!
Looks like you need to borrow a clockspring to see if that makes a difference.
The charging circuit light being on but recovering is a bit odd.
Land Rover - Turning Drivers into Mechanics Since 1948
Member Since: 01 Jan 2014
Location: Dumfries, Scotland
Posts: 84
If it was clock spring I would not get any reading at the engine ECU as I tested from switch through clock spring back to ECU. I also joined the wires from switch before it went into clock spring to were it came out clock spring( by passed clock spring) and got the same results. Any other ideas
22nd Nov 2014 9:23 pm
Disco_Mikey
Member Since: 29 May 2007
Location: Dundee, Scotland
Posts: 20780
Been caught out by a blown fuse in the BJB before. Be worth getting the diagrams out and checking all relevant fuses My D3 Build Thread
Member Since: 18 Jul 2011
Location: Stockport
Posts: 7830
Re: Cruise Control Guru Needed !!!!!
scaniaman wrote:
What else stops cruise from working?
There is something else that stops cruise working and it's the park brake relay. I seem to recall if you unplug the park brake relay, park brake stops operating, cruise is lost and anti stall stops working. TBH, I think you're barking up the wrong tree with that anyway.
If it was me, I would repair that cruise wire again underneath the airbag. Mine failed, I fixed it. It failed again not that long after so I fixed it again. When it failed for a third time, I spliced a new length into the cable giving it about an extra 50mm and soldered the joint up. No probs since.
Also be aware, the cable usually fails BUT leaves the insulation intact so it looks good, it's not. Mods:
Front Fogs + Halos
FBH Remote Control
The 1st Ever RRS Modded Grill
Garmin Nuvi + D4 Surround + Reversing Camera.
D4 Steering Wheel.
Rear Boot Spoiler.
Twin Brake Lights.
Wing Mirror Indicator Repeaters.
Long Roof Rails
Make your own Narpy grill thread
I'm not scared, I'm outta here.
22nd Nov 2014 9:37 pm
scaniaman
Member Since: 01 Jan 2014
Location: Dumfries, Scotland
Posts: 84
New loom, the old one was soldered up and worked till mid week when cruise packed in and never worked since. Thought it was my dodgy soldering so never bothered as I had a new loom sitting. Went to fit it today and things have went down hill since. New loom only done about 2 miles if lucky. Before it would always work but cut out now it doesn't work at all. Old soldered loom is OK by the way don't see two being faulty.
Park brake thing might be something, last couple of weeks I have seen the orange park brake light when switching off but clears when restarted. If I switch the ignition off and pull the park brake switch at same time it doesn't like it. If I wait till red park brake light is on then switch off all ok.
Fuses will pull all out and check as wiring diagram and handbook cryptic to say the least.
22nd Nov 2014 10:06 pm
Robbie
Member Since: 05 Feb 2006
Location: ¯\_(ツ)_/¯
Posts: 17932
scaniaman wrote:
If it was clock spring I would not get any reading at the engine ECU as I tested from switch through clock spring back to ECU. I also joined the wires from switch before it went into clock spring to were it came out clock spring( by passed clock spring) and got the same results. Any other ideas
Bypassing the clockspring changes the resistance value.
A degraded clockspring ribbon changes resistance value depending on position.
Good luck with your fault finding.Land Rover - Turning Drivers into Mechanics Since 1948
Member Since: 01 Jan 2014
Location: Dumfries, Scotland
Posts: 84
Robbie What is inside the clock spring. I thought it was an insulated ribbon bent back on its self that joined the connectors together allowing the wheel to turn. The length of wire would not make much difference to the resistance as long as it was still touching or am I wrong. Both readings were near enough for me all with in 10 ohms or same over whole system using cruise control buttons. (cold, wet, and windy and well off by then.)
22nd Nov 2014 11:14 pm
Bodsy Site Sponsor
Member Since: 06 Nov 2006
Location: In the Clubhouse
Posts: 21361
It's a ribbon, it cracks over time.
I can send you an unused one, if it fixes it, you can pay me, if it doesn't, just pay postage both ways. Bodsys Brake Bible
Clock/ SNOTM /3Flash / 4x4Info /BT Update /Service Reset/Error Codes / Gearbox Reset See It Here
22nd Nov 2014 11:30 pm
scaniaman
Member Since: 01 Jan 2014
Location: Dumfries, Scotland
Posts: 84
Anybody got a good clock spring I could purchase, as its the only part not replaced. If I found a broken connection I would be happy to buy new but not 100% convinced. Different resistances reaching ECU when buttons pressed but still no cruise. Might swap wires from radio control positions to cruise positions through clock spring to see if cruise works, if easy to do, that should tell me one way or another (Radio works fine). Sure one connector had no wire in it.
22nd Nov 2014 11:33 pm
CDS Site Sponsor
Member Since: 12 Oct 2009
Location: All over the UK!
Posts: 3330
Here you go:
Click image to enlarge
Click image to enlarge
Click image to enlarge
Click image to enlarge
Click image to enlarge
Click image to enlarge
Re-assembly is simply the reverse of disassembly
Discovery 3/4 & RRS keys cut and programmed at your home or work
Apple CarPlay/ Android Auto retro fit - see it here
BAS Remaps/ EGR Blanking
Software updates/ enabling
Mobile Servicing & Repairs
Last edited by CDS on 23rd Nov 2014 10:15 am. Edited 1 time in total
22nd Nov 2014 11:34 pm
Bodsy Site Sponsor
Member Since: 06 Nov 2006
Location: In the Clubhouse
Posts: 21361
Clock/ SNOTM /3Flash / 4x4Info /BT Update /Service Reset/Error Codes / Gearbox Reset See It Here
22nd Nov 2014 11:35 pm
scaniaman
Member Since: 01 Jan 2014
Location: Dumfries, Scotland
Posts: 84
Thanks for the offer Bodsy Will have another play tomorrow and will PM you tomorrow night.
22nd Nov 2014 11:38 pm
scaniaman
Member Since: 01 Jan 2014
Location: Dumfries, Scotland
Posts: 84
Ok latest update. Bodsy sent out a new clock spring fitted this afternoon, test run still the same no cruise control.
Removed the battery and plugs onto Engine ECU again and tested the resistances I got between the two cruise control wires at ECU when somebody pressed the buttons, got the same results as before.
Recap on items so far-
Second hand switches fitted, work but still cut out.
Calibrated clutch pedal
Replaced steering wheel loom.
Fitted bodsys clock spring. Still the same.
Checked wires from steering wheel right back to ECU all tested OK. (got same results with both switches so should be OK)
Replaced brake light switch.
Checked all fuses, all OK.
No codes.
Still would like to be able to check clutch pedal switch, 3 wires on it and no mechanical parts. Bolts onto master cylinder, must be magnet or something inside cylinder it senses. Took for run with it unbolted and still no cruise but didn't notice any other changes with it unbolted. Would like to test it or know what signal the ECU needs or what it does. When I first got the car if you went to drop down a gear when towing with cruise on the revs shot up until clutch was right down, pedal calibration sorted this, just touching the pedal cut cruise cut off.
Anybody have wiring diagram with clutch switch shown ?
Would IID tool tell you if clutch was pressed and cruise control buttons pressed ??
25th Nov 2014 10:07 pm
scaniaman
Member Since: 01 Jan 2014
Location: Dumfries, Scotland
Posts: 84
Removed plug from clutch switch and got bong of doom and park park brake fault and fault code in nearly every ecu in car . Take it as being Ok.
Back to looking at what I have found, 5 different resistances at ecu ? Think I should only be getting 4? Next to no resistance with nothing pressed, then different for each button press. Getting 23 ohms with nothing pressed bad connection rubbed wire.
Will check voltages latter, am I right in saying there should be 5 volts out ecu then a different voltage back depending on buttons pressed. Seriously lacking info, just working off how I think it should work.
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
TBH, I think you're barking up the wrong tree with that anyway.
off by then.)
