Towing Backup / Reversing Relay ?

[bjm]

Originally Posted by Gazza1

Hey Drover thanks again. Just wondering do you have any tips on fuel economy as mine has gradually drifted up. I used to get 7 or 8l/100 on long runs and about 10 around town. Now it's 11l/100 on a run and 13 around town. I have it regularly serviced so air filter like new and just done another clean of MAP, MAF and EGR tube but it made no difference. Car is still running great but not sure why consumption has gone up.

A number of things may effect fuel consumption.Inc, tyre pressures,new tyres,road surfaces,calipers dragging ,fuel filters need changing ,even thicker viscosity oils in the diffs Try running a bottle of concentrated Penrite diesel injector cleaner fo a couple of tanks.!

[drover]

My fuel economy has crept up over the years I just put it down to upping the grade of oil and tyres and possibly brand of fuel ..... I would check tyre pressure first, 4-6psi above cold pressure when they are hot is ideal, tyre placards pressure are often wrong .. I use Fuel Doktor in my tank it cleans the system though I use it to make sure the fuel is lubed up for the HP fuel pump, I did notice a slight improvement in fuel burn.... If the filters are all new then a cleaner in the fuel might help.



Again I doubt its the Jeep with the light problem, more like the plugs or leds, I would just disconnect never found a need for reversing lights on a van, mine doesn't have them and the pin is used for something else..

[Jeeper6]

I used to get 7 or 8l/100 on long runs and about 10 around town. Now it's 11l/100 on a run and 13 around town.

That is a tad high, even my Jeep with it's fat mud tyres, roof rack with awning, bull bar and snorkel all interrupting air flow...does around 11.8 litres per 100km on long runs at 100 - 110kmh...around town though it usually isn't much different...

[Gazza1]

I put a bottle of the Penrite Diesel Complete Cleaner in the other day so I'll see if there is any improvement.

Anybody else know where I can find the Tow relays in the diagram in my first post? I have lifted the flower distribution board and looked on th3 underside but it is just the multiple connectors.

[drover]

Haven't actually had to investigate trailer wiring that far, mostly just down the back but since I'm bored I did a bit of digging, my wiring diagram for the 14-17 models differs from yours but also when I look at the fuse box diagram inside the fuse box lid on mine, fuses 28-29-30-51 and 81 are for trailer, no mention of any relays at all, its not the first time I have found wiring diagrams don't quite reflect whats in the real world either ... while there are some variations to the lay out of 14/15's the tow fuses are the same and other than the wiring diagrams no other mention of relays, I don't think they exist, at least on Export models... Look under the fuse block lid.

The 11-13 actually had a trailer tow lamp relay as K6 but doesn't show up in later models 14 on.

Since its only reverse lights that have failed then I would be looking at the van wiring and lights first, bad light earth, plug disconnected or water damaged, be far more likely than Jeep.... as far as I know if the van wiring is faulty the BCM will shut down the circuit as far as I know until the circuit is safe ... it may not be a short but a bad earth or resistence causing it or a dodgy led ....

Sorry for the bum steer as to relay location, an assumption i made due to location of another relay in similar position, they are only small things.

[LeCheese]

Not sure on the relay, but whack a multimeter on the reverse light pin, get someone else to stick it in reverse (with the brake on!!!), and work backwards from there. Will at least help to narrow it down a bit.

[Gazza1]

Hi

Well I finally found what was causing my redarc tow pro to keep showing short circuit on the brake wire (and the reverse light short circuit). The numpty caravan manufacturers used massive floor fixings which have punctured straight through a wiring loom in the caravan A frame.
I definitley have a fault on the Jeep now as I ran the caravan with the reverse pin on the caravan trailer disconnectef put car in reverse and I get no voltage at trailer plug or either side of the backup (tow reverse) fuse 28. So it looks like it must have blown the relay contacts but I just can't find the darn relay.