Product Guides > Cruise Control on Fiat Ducato

Mon, Feb 11th 2013

Having been using cruise control in my car on a regular basis for around three years, I really missed it when driving the motorhome. After some research I chose the Conrad-Anderson GC30 & CM19 kit with vacuum servo and right-hand stalk command module.

Stalk command module

General Notes

First ensure that any work will not invalidate any warranty on the vehicle.
Solder the joints where possible - more reliable.
Use cable ties to keep wiring as tidy as possible and away from throttle actuating lever - safety implications.
Legends on Control Module don't match instructions: where SET is mentioned, use FIX/KM+ and for RES use MEM/KM-.
Use a multimeter to determine "live" wires on brake switch etc. The colours mentioned in the text may not match those on your vehicle.
Put any removed parts carefully to one side with their screws.

Tools & miscellaneous parts

Set of blade and pozi-drive cross-point screwdrivers.
Set of Torx drivers (up to size T40).
Soldering iron (25W minimum - 60W temperature controlled preferred).
Hacksaw, drill, drill bits, files etc.
Cable ties (Nylon ratchet 2.5 x 99 and 3.5 x 150 approx.).
Nuts, bolts and washers.
Insulation tape
The fitting kit provides most other parts required.

Dashboard removal

First remove lower steering column shroud - 4 self-tappers. Then remove upper shroud - two concealed self-tappers right at the top - use a torch!
Remove fuse-box cover and reach inside to the left to find latch which unclips the diagnostic connector cover. Remove it.
Remove the right-hand dashboard oddments tray to expose a concealed dashboard skirt section securing screw. Remove the "skirt" section - total of 4 self-tappers and a Torx plus clips and locating studs - it's a fiddle! Watch out for the screws hidden behind the bonnet release and steering wheel adjustment levers.
Removed headlight up-down adjustment cover panel and matching blank on the other (driver's side) of the steering column. This reveals two hidden screws - remove these plus the two behind the speedo/rev counter binnacle (behind the windscreen on top of the dashboard).
Remove the binnacle and release and un-plug the three connectors. Protect the binnacle with a cloth to prevent scratching.

Throttle actuator

Attach to power steering fluid reservoir mounting bracket using two right-angled brackets under the reservoir fixing.
Fit the unit upright, with vacuum connection at the top, to allow any moisture to drain out of the small hole on the opposite side to the vacuum tube. The curved fixing provided with the unit will require re-orientation to suit.
Run the Bowden and signal cables through a hole in the bulkhead. There is an un-used grommeted hole above right of brake servo when viewed from front. Temporarily remove nuts and rubber cover from the end of the Bowden cable to ease the task. A drop of washing-up liquid works wonders for lubrication!
Route the Bowden cable, in as big an arc as possible, around under the dashboard to a point adjacent steering column "box" bolt. Remember that, when the skirt is re-fitted, the housing for the steering wheel adjustment release lever will occupy space in this area.
Cut the vacuum tube to the brake servo using a knife, backed by (say) a wide chisel blade. Don't saw in order to avoid contamination of the vacuum system with plastic dust. Remove a length of tube to suit the adapter. The small white adapter, supplied in the kit, is the best fit. Use cable ties or small clips to secure the tubes. Clips are best on brake servo vacuum pipe as it is hard. Cable ties can be used for tube to servo. Take great care here as a vacuum leak may affect engine and, especially, brake performance. As vacuum connections are self-sealing to some extent, a tight fit will probably render clips unnecessary. If you do use clips, make sure that they don't ruck the pipe.

Throttle actuating lever

Use a length of steel strip approx. 210mm long by 20mm wide by around 2 to 3mm thick for the lever. A short length of the same strip may be used to make the angle bracket which prevents rotation of the lever in relation to the accelerator pedal. The finished angle bracket should measure around 20x30mm when finished. Stud and angle bracket securing screw holes should be about 8mm from the lever ends and there should be around 25mm between the fixing hole and angle-bracket securing holes. It may be possible to use the long strip supplied with the kit or Conrad-Anderson will supply a ready-made lever assembly, at additional cost, on request. A stroke of about 40mm is required at the point of attachment of the throttle actuating Bowden cable.
Drill holes and fit the throttle lever to allow as straight a run as possible for the Bowden cable inner. See sketch supplied with the kit for more detail.
Remove accelerator pedal assembly and release and unplug the electrical connector. Caution - don't switch on the ignition whilst the accelerator is un-plugged.
Remove pedal fixing screw and (preferably, using a new longer screw) attach the actuating lever. Offer up the modified assembly to the vehicle and ensure that the full swing of the lever and pedal are un-impeded by any vehicle parts (eg. wiring harness - of which there are many!). It may be necessary to bend the lever to bring the end of it into line with the Bowden cable fixing bracket hole. I found about 5 degrees to be necessary. Use as small an angle as possible. It may also be necessary to elongate the lever bracket hole in order to adjust the position of the top of the lever clear of any obstructions. Take time and care over this - it will pay dividends. Remember that the cruise control has safety features but it can't compensate for a jammed throttle actuating lever!!
Remove assembly and carefully tighten all fixings. I used some thread-locking compound on the accelerator fixing screw for added security and safety.
Refit the assembly and re-fit the wiring connector. Operate the accelerator pedal over it's full travel and ensure free and un-obstructed operation.
Use the kit parts to secure the Bowden mounting below the securing bolt. Use washers each side of bracket and secure with another nut in order to "stand-off" the bracket from the box/bolt. There is no need to remove the original nut as it makes a good spacer and there is plenty of spare thread.
Ensure that the cable is accurately aligned and then fit the solderless nipple (it's a "fiddle" but makes sure that the allen screw is really tight) ensuring that there is a little bit of slack and plenty of adjustment both ways on the outer cable fixing. Adjust as necessary for minimum slack then ensure that the lever operates freely leaving the Bowden cable inner free to slide in the stud hole.

Control (command) module

I used the right-hand "stalk" unit fitted to the upper steering wheel column shroud above and behind the ignition switch. The fixing hole may be conveniently drilled on the bench with the stroud removed from the vehicle.
There is no need to drill a hole for the cable as it passes nicely down through exiting gaps in the dashboard trim.
Carefully fit the 4 wires into the 8-way connector ensuring that the colours match. You only get one chance so "get it right" don't have to "put it right"! Ensure that the pins are inserted correctly by observing the shape of the pin and pin housing.
Tape back the linked 3-way connector unless using the memory control module.

Cable harness/electronics unit mounting

Fit connector and use cable ties to steady the cable form
Cut off the yellow (tacho) wire around 75mm from the logic box (before suppressor) and insulate the bare end.
"Mount" the electronics module among the wiring etc. on top of the drivers-side wheel arch.

Brake switch wiring

Connect brown wire to switched side and brn/wht wire to "live" side of switch. Both wires must be connected.

Clutch switch wiring

Connect mauve wire to grey/white wire on clutch switch. Switch may be removed to ease this task as it has a bayonet action. I used an IDC (Scotch-Lock) connector here owing to restricted space and little slack in the cable.
Note that action of clutch signal is inverted compared to brake. Signal is normally at nominal +12V DC and goes to 0V when clutch operated. This doesn't matter - it's edge triggered.

Speed sense wiring

Join the blue wire of the blue/back pair onto pin 1 of the middle connector behind speedo. Salmon/blue wire. Fold back and tape the un-used black wire.
Don't be tempted to use the white wire on the back of the radio - it may not be connected - mine wasn't.

Supply wiring

Fit green earth tag under screw lower right of dashboard.
Join the look orange supply wire to the orange/white wire from the ignition switch. Don't fit the fuse yet.

Safety

Ensure free operation of throttle actuating lever. Use cable ties to secure adjacent wires in order to ensure that they cannot move to impede movement of the accelerator etc.
Check that vacuum connection
Visually check all wiring at this point before fitting the fuse in the holder in the orange supply wire.

Diagnostics

After fitting the in-line fuse, put the system into diagnostic mode by switching off the ignition, holding down the "FIX" button and then switching on the ignition. Press the ACT/OFF button to illuminate the green LED. Release the FIX button after switching on the ignition.
All functions (eg. brake operation) will cause a short bleep if "seen" by the electronics unit. A long bleep indicates a fault. Remember that the clutch signal is inverted and this will initially cause a long "error" bleep - ignore it.
To test the vacuum servo, first put the system into diagnostic mode but start the engine immediately after switching on the ignition. Press FIX and hold it until engine speed increases. Release to obtain constant speed then press MEM/KM- to reduce it. Press ACT/OFF to disengage the cruise. Switch off the ignition to exit diagnostic mode.
When in diagnostic mode the vehicle may be driven. Listen for bleeps as speed signals are detected. The frequency will increase with increased road speed.

Set-up

Follow the instructions supplied with the kit for initial set-up etc.
I found that it was only necessary to follow the initial set-up procedure to get an instant result.
Re-instate the dashboard parts in reverse order.

Conclusions

Conrad-Anderson were extremely helpful in offering advice prior to the installation and supplied the throttle actuating lever at additional cost.
The basic instruction left something to be desired and were re-hash of those for an earlier model. Initially the up-to-date wiring diagram wasn't supplied with the kit but was quickly provided when the fact was pointed out. The set-up instructions were very good apart from the minor problem of legend mis-match.
Conrad-Anderson are currently sorting out the instructions and informed me that fitting is similar on Mercedes and Ford vehicles.
On the road the unit works very well indeed with good pick-up, smooth control and good, fiddle free, accuracy.
Result - an enjoyable project with satisfactory results at reasonable cost - enjoy!!

Reproduced courtesy of:
Motorhome Monthly, incorporating RV News - September 2003

Add a comment...

Please login or register to comment.