Disco 3 electronics problem

On 05/01/2011 18:01, Ron Lowe wrote:

Transmission limp home mode? D2 drops into 4th convertor drive if fault
arises when driving, 3rd convertor drive if fault exists on start up.
Very sluggish. Has something similar happened?


Chafed wiring. My D2 earthed itself against the gearbox casing: was
worse when the contact area was wet.

Hi, all.

Disco 3, 2.7l TDV6 06 plate.

Driving at constant motorway speed, and:

BONG: HDC fault, HDC unavailable
BONG: Transmission fault
BONG: Suspension lowering.

Terrain response programs unavailable.
Unable to raise suspension.
Transmission does seen to function in auto, but feels sluggish.

Turning off vehicle and re-starting clears faults for half a mile or so.
Then same sequence of bongs and faults.

Sent to independent garage, still there.

Googling suggests:

-Brake light bulbs ( yes, really! Aparently, if the filament in a
dual-filament bulb fails in such a way that it can touch the other
filament, this causes no end of mischief in the electronics! )

-Corroded wiring / connectors in wheel-arch areas;

-Battery.

Anything else?

--
Ron


Could be any number of things I'm afraid, needs a main dealer to hook up to
Test-Book to see if any fault codes are stored really.

Only oddball one on the D3 is the brake light circuit, have you got any
brake light bulbs out or have any recently been changed? There is something
odd in the circuit that can throw out all sorts of errors if the resistance
is out of the normal limits.


Andy

< 1999 D2 TD5 GS Auto >
< 1996 D1 300tdi >

On or around Thu, 6 Jan 2011 13:41:01 -0000, "Andy Cooke"


it's not alone in that.  failed brake light fuse in the disco II leads to
spurious difflock light and bongs when you press the brake pedal, on a
vehicle with no diff lock!

On 05/01/2011 18:01, Ron Lowe wrote:

Well, Independent LR garage put it on their autologic diagnostic
doo-hicky and it's reporting the brake light switch producuing
'inconsistent output'.

Further testing by myself gives this result:

1) During driving, the fault in intermittent, but when it occours, it
occours on releasing the brake pedal.

2) With the car powered-up, but without the engine running, the
following is observed:

With the transmission in P, pressing and releasing the footbrake causes
the interlock solenoid in the gear handle to go click-click as expected.

Repeatedly depressing the brake pedal: click-click. click-click.
click-click. silence.   Suddenly, the interlock solenoid is no longer
operating.   The transmission can be pulled into gear without applying
the footbrake. BONG BONG BONG all reported faults present.

So I'm fairly confident in the diagnosis thet the brake switch is
goosed.   It must have multiple contacts, and they are not all jiving
together.

The replacement will be fitted tomorrow or next day.

--
R

On 05/01/2011 18:01, Ron Lowe wrote:

Well, Independent LR garage put it on their autologic diagnostic
doo-hicky and it's reporting the brake light switch producuing
'inconsistent output'.

Further testing by myself gives this result:

1) During driving, the fault in intermittent, but when it occours, it
occours on releasing the brake pedal.

2) With the car powered-up, but without the engine running, the
following is observed:

With the transmission in P, pressing and releasing the footbrake causes
the interlock solenoid in the gear handle to go click-click as expected.

Repeatedly depressing the brake pedal: click-click. click-click.
click-click. silence.   Suddenly, the interlock solenoid is no longer
operating.   The transmission can be pulled into gear without applying
the footbrake. BONG BONG BONG all reported faults present.

So I'm fairly confident in the diagnosis thet the brake switch is
goosed.   It must have multiple contacts, and they are not all jiving
together.

The replacement will be fitted tomorrow or next day.

--
R


So I was pretty damn close then :-)

Andy

< 1996 D1 300tdi >