Outer Limits 4x4 Board

OK, Im not quite a dumb blonde when it comes to cars EXCEPT when it comes to figuring out the electrics - or electronics.

I have a GUIII, 4.5litre 5-speed auto ST wagon. Purchased it second hand about 3 months ago with 157k on the clock, good service history etc etc etc.
It had never been offroad.

I had LPG installed (injected) which necessitated the main tank being taken out and replaced with the LPG cylinder, and a new 75litre after-market petrol tank installed where the former sub-tank sat between the chassis rails. The end result of this was the permanent lighting of the 'sub-tank' light on the dashboard. I can live with that.

However, a newer, nastier event has started. Sometimes the electronics of the dashboard just stop appearing. That's no fuel gauge, no tacho, no speedo, no gear indicator, no odometer, no trip meters, no temp gauge. Sometimes it happens when I start the vehicle, sometimes it just happens while Im driving. Sometimes its when Im out 4WDing, sometimes when Im in suburbia on the tarmac. Its happened sometimes that Ive started the vehicle, had no dashboard and driven 100m before it's kicked in. *shrugs* no set pattern. When I lose the dashboard, I also lose the ability to manually change down gears and the central locking is disabled.

The emergency lights work, the indicators work, the headlights work; its just those abovementioned parts of the dashboard - y'know, the IMPORTANT parts!

So far, the only way that I've figured out to restart things again is to take the battery fuse out - essentially resetting the electronics. The odometer has still been registering (it does change), but everything else reverts to zero (the clock, the trip meters). If I wasnt doing any 4WDing I probably wouldnt worry - but being unable to downshift the gears and drive in low range/1st gear downhill when its too slippery to use the brakepedal is horrifyingly real!

So my question is... what's causing it and how do I fix it? Take it back to Nissan, pay a fortune to have it (hopefully) figured out, or take it to an auto electrician? Is it a problem with the engine management computer or is it just an intermittant short? I got no idea of where to start with this one - any help gratefully accepted!

Auto lec

Nissan will just be trying to rip you off.

Check your earth leads.

You may need to attach additional earth straps to the body or chasis or both.

Your problem is a known one

Have seen this fault before on a GU, it was in the eletronics in the dashboard. We replaced the instrument cluster, which is quite costly.
Steve

A friend of mine had the very same problem with his gu III. His is a TI model with TB48 motor. His problem started just after his LPG conversion. We took it back to the gas fitter and demanded they fix it or else. It took some convincing but they had it at an auto elec for a few days, it cost them more than they made from the conversion.

My GU was doing a similar thing,

All gauges dropped out while driving and would come back when they felt like it.

I took it to an instrument repairer, who sent it to someone in Sydney and had the cluster repaired. Cost me about $300 to repair.

not much help however the clock and trip meter will be going to zero as you are taking the electronic parts fuse out wich powers these things...

Update... I took my baby to an auto elec along with all the suggestions (thanks guys!). He installed heavier duty earth straps, along with a new
earth from the subtank to the chassis.

Nearly two weeks on and there's been no issue. A bonus has been the petrol tank gauge has actually stayed on full (since it is full, minus maybe 2 litres) throughout three tanks of LPG. Before the new straps, it would have used about a litre (the car starts on petrol, then switches to LPG) and the fuel gauge would have gone to empty and the low petrol warning light would have illuminated. Which necessitated having to drive by km on the contents of the petrol tank.

Since tomorrow is Sunday and Im going out playing, I'll be giving my baby a bit of a workout, so hopefully she wont play up.

Thanks again guys for your help!