Disco 2 drive problem

Hi, I have a 2000 Discovery TD5 Auto, which has a fault my mechanic is unable to fix, without any prior warning
the green M and F lights come on and flash, plus the orange engine management light comes on ,when this happens the throttle does not work the engine remains on tick over the gears still engage, I have had a new injector loom, a new heavy duty battery, the oil cleaned from the ecu loom plug, and the fault codes cleared that was four weeks ago and all was ok until today when it did it again and left me stranded on a junction. After approx half hour of turning it off and on I got full function back and drove it home, anyone got any ideas whats wrong with it ? any help will be much appreciated

Hi, you have two things to do:
1. replace the injector loom pronto untill it doesnt hurt something and keep cleaning the red plug untill all the oil leaves the harness
2. replace the throttle pedal which is together with the sensor, that's the main cause of the warnings and no driveability

Hi Many thanks, I will buy a throttle pedal unit, and check the red plug, the injector loom was replaced with a new genuine land Rover one four weeks ago so hopefully that will be ok?

Then just keep cleaning the red plug once a week untill it stays dry

Hi, I brought a throttle pedal secondhand off e bay, my mechanic (who is not land rover trained) fitted it, he checked the red plug on the ecu which was dry, he then scanned it and loads of can bus faults came up, he cleared these and the disco worked, well for 11 miles it did then broke down again with no throttle action engine just on tick over, it still has drive and reverse, but again both the green M and F lights flashing and the engine management light on, my mechanic is guessing that the ecu is shot and tells me that these are coded to each individual vehicle and therefore are not interchangeable, is my Disco scrap ? what can I do to repair it, any help much appreciated

we should know the exact description of those fault codes though, and the transmission ECU must be scanned as well preferably with dedicated tester not generic one...it's a long way untill the ECU can be blamed especially if it drove 11 miles and now the symptom is different

I have had my disco scanned with a Snap on Scanner by a mobile mechanic, he cleared the codes which stopped the M and S lights flashing and put the engine management light out he started the engine and the throttle action worked with the engine revving as it should, he then re-scanned it and no fault codes showed, he told me that the disco does not have a live fault, but an intermittent one. The fault codes found were as listed below.


7 Manifold pressure circuit fault
13 driver demand supply fault
14 Ambient pressure circuit fault
92 EGR valve stuck closed (this was blanked off by the previous owner)
93 Driver demand 1 out of range
94 Driver demand 2 out of range
95 Faults detected driver demand

The chap who scanned my disco has no idea what these fault codes relate to, any assistance will be much appreciated, i am unable to use it as when the fault appears I have no throttle just idling !!!!, and have to be recovered

All th driver demand fault codes are related to the TPS(throttle position sensor) signals and can cause the symptom you describe...the others can affect engine power but not else...if the TPS was replaced with 100% good one the problem is somewhere between the TPS and ECU or within the ECU, as long as there is not a problem with the connection in the ECU black plug where the TPS inputs are other contact problems might be in header C0294, very hard to access it's embeded in the harness

Hi Many thanks for your assistance, the only sensible way forward for me is to book it into a Land rover specialist as it's a bit to technical for me to deal with, I will let you know the outcome in the hope it will help other disco owners who get a similar problem
kind regards. Peter

I have been told that the throttle pedal switches (sensors?) have to be adjusted to bring the throttle into the correct range does any of you know what the settings I need should be ?

I thought it was just plug and play.

In the workshop manual, it does not state anything about adjustment when replacing the unit.

But I may be wrong.......

Cheers

smitpet said:

..... the throttle pedal switches (sensors?) have to be adjusted....

Click to expand...

not on a D2 that's for sure, it's plug and play all the way

smitpet said:

I have had my disco scanned with a Snap on Scanner by a mobile mechanic, he cleared the codes which stopped the M and S lights flashing and put the engine management light out he started the engine and the throttle action worked with the engine revving as it should, he then re-scanned it and no fault codes showed, he told me that the disco does not have a live fault, but an intermittent one. The fault codes found were as listed below.


7 Manifold pressure circuit fault
13 driver demand supply fault
14 Ambient pressure circuit fault
92 EGR valve stuck closed (this was blanked off by the previous owner)
93 Driver demand 1 out of range
94 Driver demand 2 out of range
95 Faults detected driver demand

The chap who scanned my disco has no idea what these fault codes relate to, any assistance will be much appreciated, i am unable to use it as when the fault appears I have no throttle just idling !!!!, and have to be recovered

Click to expand...

Many times it's been posted on these boards that a user has had his Disco 2 scanned by so-and-so mechanic using a such-and-such professional code reader and found some inexplicable faults. The fault codes must be right, because it's a garage with for example, a "Snap On" scanner; right?
Sadly, because of the lack of full OBDII compatibility found on the diesel Disco 2 electronic systems, there is the possibility that a) the indicated faults don't exist, b) faults exist on the vehicle systems which the scanner used cannot detect or c) the scanner in use has detected faults but is unable to interpret them correctly.
The problem becomes even worse when one realises that the only professional diagnostic equipment guaranteed to give sensible results (though not always sensible invoices) is an up-to-date Testbook T4 system as found at a Land Rover dealer. For the DIY home mechanic the only other alternative is to use one of the known compatible code readers such as Nanocom, Hawkeye or Lynx.
Erroneous readings can often lead to false information, a classic example is a user being advised that the throttle sensors are "out-of-range" and must be adjusted because the professional level scanner says so but as @neilly and @sierrafery have pointed out, the unit in question is "plug-n-play" and has no adjustment.

I am very grateful for all of the above responses, however I am not "technical" and if I had one of these scanners would not know what to do with it, is there anyone who is mobile, and knows how to fix the problem i have? as it is at the moment my disco parked up and out of action.