Thoughts and advice on the care and feeding of fine automobiles from Machine Aficionado and bestselling author John Elder Robison, owner of JE Robison Service in Springfield, Massachusetts

We are independent restoration, repair, sales and service for Audi, BMW, Bentley, Jaguar, Land Rover, Mercedes-Benz, Porsche and Rolls-Royce automobiles.

Bentley archives

Land Rovers

electrical problemL322land roverrange rover

No starts and weird electrical gremlins in 2008-2012 Range Rovers

Lately we have started seeing 2008-2012 Range Rovers that don’t start, lose their displays, or behave erratically.  When scanned for faults we find CAN communication faults and it’s clear some part is failing and bringing down the data bus.  When the bus is down the car can’t pass the security information and it won’t start.  If it’s running it may lose any number of functions.

2011 L322 Range Rover HSE

On several occasions we have traced this problem to water intrusion into the electronics compartment in the left rear.  In particular there is a park assist module that’s installed with its case facing up, so it can fill with water and corrode.  We have now seen several of these units destroyed in this way and suspect there are hundreds if not thousands in the field with the same issue brewing.

The park assist module is connected to the CAN bus, and if it shorts and brings the bus down, there is no predicting what will fail.  The nature of this kind of corrosion – based as it is on water sloshing inside a module – means the fault may come and go for a long time before becoming permanent. 

As electrical systems get more complex there is greater reliance on data bus as opposed to dedicated wires for intra-car signaling.  Such circuits are more prone to disruption from corrosion than traditional wiring.  That means the wire harnesses and plug junctions are increasingly likely to be trouble spots.       

© 2018 John Elder Robison

John Elder Robison is the general manager of J E Robison Service Company, celebrating 30 years of independent Bentley, Rolls-Royce, BMW/MINI, Mercedes, and Land Rover restoration and repair in Springfield, Massachusetts.  John is a longtime technical consultant to the car clubs, and he’s owned and restored many fine British and German motorcars.  Find him online at or in the real world at 413-785-1665

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