Mark Barrett

Guys Apologies for the long post, but need to kinda explain where I am with this in order to ask my questions at the end. Also apologies as I have also posted this in the Electronics section to try and reach as many poeple as possible. I have an RX300 SE Navigation (series 1 2002). A few weeks ago the Boot mounted DVD unit for the SatNav expired - I am pretty sure it was due to a careless valeter spilling chemicals on it, but as I didn't use the navigation for a few weeks afterwards I can't prove anything) - Anyway I have taken the unit apart and the PCB has clearly suffered water damage and fried the PBC as a consequence. I was getting an "external unit is no connected" error when I tried to use navigation meaning that it couldn't see the unit as being there. I have been lucky enough to source an alternative unit from eBAY - came with Boot mounted DVD player, Audio head unit and screen and CD Multiplayer from glovebox. I installed the new DVD player this afternoon, and it is now seeing the DVD unit (as it is asking to load disk etc), but after the "reading disk" cycle it then asks me to open the disk door and check the disk. This is as far as I have got. So there are a number of reasons that I can think of for this, and I am looking for hints as to which way to go before I start ripping the car apart: Are the headunit and DVD unit a matched pair? i.e. if I change one do I need to change both, or is the system not that clever? The DVD unit carries the same part number as my broken one, but didn't know if there was different software variants on the same part number? Can I move up and down software versions by changing the disk? I now have a v1.02 and a v1.01 - should both work, or once you have moved up to a newer version you can't go back again? Audi for example, once you have gone up a version then it will throw an error if you go back down. Does anyone know how many potential errors the "Check disk" message covers? Is it a simple case of the disk not being read due to being scratched, or could it be a wider range of problems like software imcompatibility? I didn't know how wide a range of errors the unit is capable of reporting. I may be able to recover the DVD scratches, but I know the Lexus units are sensitibve to scratching, so I may be able to recover it on a PC to make a copy - I need to make it clear, this is NOT PIRACY, this is just making a second copy of a disk that I already own. I would be interested to know if these disks are successfully copyable - if people are uncomfortable replying in main page then a PM is fine. Although I am competent electrically, I am not Lexus experienced, so any advice would be greatly appreciated Thanks Mark

Chris Thanks for your tip - it was indeed towbar wiring. Whoever installed it (and I am not sure as I bought the car secondhand) routed the 12V feeds for the electrics through the inner cwing and into the door jamb - but did not grommet where it went into the car. My best guess is that the wire was worn away over time as the door opened and closed and eventually shorted to the chassis. The fusepack saved the rear wiring, but the wiring from the fuses forward to the battery were shorted and caught alight Thank *** my wife wasn't driving, she would have struggled to know what to do, and fortunately the wires managed to avoid melting anything else in the loom, so no long term damage. I have cut all the wires out and reverted the rear lights to "normal" - i.e. cutting out the towing relays etc etc. I will worry about rewiring it when the weather gets better Bloody cars!!! Cheers Mark

Hi Chris Yes, you're right, the vehicle does have a towbar - would that be wired directly to the battery? I had assumed that towbars were just wired to the lighting circuits on the rear? Thanks for the swift response Cheers Mark

Hi all Have another problem with my "Friday afternoon" 2002 RX300 that seems to have bits dropping off it every month!! Last night I had a small electrical fire. The car still started, drove and headlights and wipers worked, but there are 2 wires under the bonnet that are melted their entire length (including through the bulkhead) I am trying to work out what these wires might power so that I can isolate the problem They are both red wires of small diameter and run directly from the battery +ve terminal around the engine bay and through the bulkhead (I assume to the fusebox). They look to have been hand wrapped, so I am wondering if they are dealer fit options rather than factory fit - the car is fitted with SatNav, Rear Park sensors and alarm as "proper" options, but not sure if any of those are dealer fit requiring additional wiring to be added Any help would be appreciated Thanks Mark