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The rear door windows are controlled directly from the BECM.
The front door windows, and the mirrors, are fed from the appropriate door outstation.
So I suggest it's not the BECM.
It's unusual, but not impossible, to have one touch operation on the rear windows. What is happening when you try to 'set' the Left Rear window?
If the mirror moves outwards but not inwards it is more likely to be an internal mechanical fault in the mirror head.
It's also possible the mirror head is set in the wrong basic position (there are two - you move the complete head by hand). In this case there simply isn't enough movement in the adjustment to compensate.
 

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Chas said:
It's also possible the mirror head is set in the wrong basic position (there are two - you move the complete head by hand). In this case there simply isn't enough movement in the adjustment to compensate.

I vote for this.
 

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x2. i was alot happier once it dawned on me :oops: the driver and passenger mirrors are not necessarily folded to the same position to get the best rear view, no matter how much you try and move the glass on them. i think i keep the passenger folded out one "click" further than the driver.
 

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Discussion Starter #5
When I try to set the LR window it says Fuse 12 fault. The mirror won't go down at all. Fuse is not blown. I set the passenger mirror a click closer. The glass itself won't still won't move inward, but the its position now allows me to view behind like I should.
 

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Hand book states that the mirror will be to be moved in one notch more from lined up position on bracket, if this dont help removing mirror (pheweee) stripping down and cleaning may resolve the issue
 

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I regarding the mirror issue as fixed. If you feel it isn't, but the adjuster will move outwards, then the only thing left to do is a physical examination of the mirror by dismantling.

The Left Rear Window. If the fuse was failed there would be a Message Centre warning all the time.
Fuse 12 also powers the heated rear window, do you get a Fuse Fail message if you switch the HRW on?

The fail message only appearing when you try to power the motor is not a situation I recall working on before.
Options appear to be:
High resistance fault in the wiring to the motor, allowing some current to flow, thus activating the monitor circuit.
Low resistance (earthing fault) but this would tend to blow the fuse.
Straight disconnection in the wiring to the motor, but I suspect the monitor circuit would not activate, because no current is flowing.

Of the wires going to the motor, the Black is Earth (Negative 12 volts),
S (Slate) is Positive 12 volts to power the window up,
SO (Slate Orange) is Positive 12 volts to power the window down.
I'm not sure which is simpler to access, but I would access either the connector in the Left Hand B pillar*, or the connector to the motor itself, unplug the connector, and apply power to the appropriate pins leading to the motor, to see if the motor moves when directly powered.
There are several connectors in the LH B pillar*, you want the Yellow one, with 6 wires in a single row, of which 1, 2, & 3 are Slate, Slate/Orange, and Black, respectively.

LH B pillar*.
The manuals say the connector is behind the door trim panel, but I suspect this is wrong.
The wiring between the door and the bodyshell goes through a concertinaed protective sleeve. If you pull this sleeve away from the pillar I think the connectors will be visible. IE, there will be enough slack in the wiring loom for you to pull them, one at a time, through the hole in the pillar you have just exposed by removing the protective sleeve.
When they build the cars they build to doors as one piece, then test them (door locks, windows, speakers) so they know they don't waste time fitting faulty units to the car. Therefore it makes sense, as with the front doors, to have the connectors outside the door itself, which of course puts them in the relevant pillar.

Regards.
 

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Stier said:
I do get a Fuse 12 fail message for the heated rear window.
In that case nearly everything I wrote after I asked the question was wasted effort, because that puts the circuit failure in the 'common' section, which is around fuse 12.
As the fuse is in the BECM this does indicate an internal fault, although it's one I've never experienced myself.

There are no circuit diagrams for the BECM, although people have opened them up and repaired them. There are two big circuit boards, one could be called the 'logic' board, which is probably 'very, very difficult' (impossible) to repair, the other is the Power board which has relays and the switching diodes on it. The switching diodes provide the 'fuse monitor' circuitry. These components are big enough to clean and repair, although as they are obsolete items obtaining replacements can be difficult. Someone on here was looking to obtain a supply, but I've forgotten who, or whether he was finally successful.

Anyone working inside should have some experience of working on electronic circuits, but anyone can, if they are reasonably sensible, and prepared to do some Searching and reading, take the top off and look.
Not a 5 minute job, as the seat needs removing.

Unless you have a real yen to go on the technical challenge I suggest you accept the slightly easier challenge of getting a second-hand replacement. You need to trust the seller, and feel confident you can send it back if the new one has a different fault. If you update your profile to say which country / state you are in others may suggest suppliers 'local' to you.
 

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I'm not too sure on either the costs or the detailed options which an Independent using either Autologic or Rovacom can provide.
Searching the forum might provide some indications, or other Americans might care to offer information.
Note this OLD thread which someone has just resurrected, but do note that information on repairers is not current.
Also note that John Brabyn has obviously got a section on BECM repair on the main site, which might give you some of the answers you want.
The only item I do recall from the Blackbox forum is that it's better to leave the BECM unlocked.
You MIGHT be able have the EKA function enabled.
This reminds me that there might be some information in the Diagnostic Forum on this site. As the MD of Blackbox contributes to that forum you might precis the relevant points we have determined and then ask your last question.

"precis the relevant points" - No message until either HRW or LH rear widow 'operated', when Fuse 12 failed message appears. The conclusion this is an internal BECM fault. (Also link back to this thread, just in case someone wants the detail of 'the process so far').

Good Luck.
 
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