Thread: D2 Under Bonnet Noise with Engine Off

Normal ... Mines done that for years.. Also Known as the Space Invader Noise ...

I traced mine to the ABS relay. I know the ABS and SLS ecu's never sleep, and I hear noises from the SLS compressor area too, so I guess it is just normal. I do keep an eye on the battery voltage because my D2 sometimes sits unused for a couple of weeks. (too many Landrovers to choose from :-)

Cheers,
Terry

Yep, same on mine. Normal. Sounds like a cricket.
Regards
Robbo

Been meaning to do this to mine: http://www.aulro.com/afvb/showthread.php't=115399

Guys, that issue with the clicking is not normal for the engine bay area(just that it happens in real life), it can be considered "normal" with some indulgence for the SLABS ECU area cos it has a counter in it for the SLS management of the compressor duty cycle, the system was conceived to stay under power up to 1.5 hours after ignition was off then go to sleep and wake up on open door signal, but only for the SLS side of it so NORMALLY it must not have any influence on the ABS modulator ...period.

Now, i know it happens to some of them but not to all as mine i think is within the "normal" ones cos it makes that noise only from the SLABS area, not from engine bay area and it stops as it's suposed to in less than 1.5 hours... i asked around those i know personally with D2s and my statistic untill now is in favor of the normal behaviour from 6 cases...3 are "normal" as mine so + mine are 4 and 3 are behaving like it was described here with noise from engine bay area too, but all are stopping within 1.5 hours ...for those cases when some impulse gets untill the ABS modulator there must be some capacitive reactance within the ECU or parasitic transfer of some voltage through the circuits or something as the ABS side of the SLABS must not be active with ignition off...at least that's how it should behave and it was conceived to... IMO if it lasts more than 1.5 hours there's a problem with the SLABS ECUs counter.

Originally Posted by RAVE-REAR SUSPENSION-DESCRIPTION AND OPERATION 64-17

.....
The ECU incorporates a counter which times the operation of the SLS system and prevents the compressor
exceeding its duty cycle. The ECU can remain powered for up to 1.5 hours after ignition off is sensed to allow the
counter to continue running to avoid an ignition cycle resetting the counter.
Opening any of the doors will power up the ECU, irrespective of ignition switch position. The door open signal is
sensed by the door switch completing an earth path which is sensed by the ECU. The ECU cannot differentiate
between any of the doors. The door open signal powers the ECU for up to 30 minutes to allow the vehicle to re-level
when a load is removed or passengers leave the vehicle.
.....

would be interesting to make a poll on this to see how many are "normal" and how many are not... and if it happens to those on coils too or not(i have a feeling that those set on oils dont have that problem)

I am sure mine's not really normal - just slightly demented

Terry

Thanks all, at least I'm not going crazy and starting to hear things that aren't there. I'll leave my bonnet open and double check if it is still going 2hrs later.

Mine is on coils and has always made the noise for as long as I have owned it. 2001 TD5 auto