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Hello,

I am having communication issues with my 2006 LR RR 4.2L SC. The high speed can bus appears to be down/intermittant. Modules on that network include IC, TCM, PCM, ABS, etc. All of wich are not communicating with autel scanner. SDD usually does communicate, but scanning of module results different many times. Sometimes communicate and others not.

I also need good source for a spare key FOB of high quality.

If you respond, please be highly qualified. As I am using my LR for a cross country trip/move.

Thanks.

Steve
 

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Have you checked your rear hatch for water leakage? Shorted pins will take down the bus. There was a guy on youtube that found the parking module corroded, shorting the bus. I can't find the video though.
 

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2002-2005 Range Rover MkIII / L322
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intermitten canbus failure is fairly difficult to diagnose and would require a multi-channel scope and a lot of time. if you can narrow it down to offending control unit, this would help with diagnostic but that means unplugging each one by one. otherwise you will need to find an experienced diagnostician and pay for the time, which will not be inconsiderable.
 

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Did a quick study on CAN. Twin wire where each lead has a voltage "bias" of 2.5V. Uses a differential signal or difference between the Hi and Lo wires to form the serial bit message. This technique is done for noise immunity.

If a module craps out, unlikely that it will ground out the bus, unless it's been seriously shorted or cooked. Water getting into a module could do this tho.

Corrosion is the likely cause because when it gets bad, residue shorts the + and - leads, dragging the whole network down.
 

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Hi, I had been having exactly the same issues as you and also using an Autel scanner could not communicate, though my thinktool scanner could but just gave "canbus" fault error codes in many systems. I finally traced the problem to the parking distance control unit in the rear being water contaminated, also the amplifier for the radio etc was the same, swapped out both units for good used off ebay and have had no canbus or other issues come back so far but no doubt now saying that next start she will treat me too some lol. My advice is rather than getting bogged down in deciphering canbus operation check the modules for water contamination first, its easiest way forward and these two units are notoriously at risk for water intrusion on L322, also check behind both front kick panels as the ecu's there can be at risk also. Hope this helps, any corrosion will bring the canbus down on these L322's in the weirdest ways that you cannot imagine.
 

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2013 Autobiography RRS 5.0SC...
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My 'ol '03 L322 Range Rover Vogue had water leaks in the rear door past door seal into boot well and caused CanBus errors this was a real concern....also LH rear quarter panel had water ingress around Audio components 2nd problem...the bus system on these vehicles is notorious for breakdowns.
 

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Hello,

I am having communication issues with my 2006 LR RR 4.2L SC. The high speed can bus appears to be down/intermittant. Modules on that network include IC, TCM, PCM, ABS, etc. All of wich are not communicating with autel scanner. SDD usually does communicate, but scanning of module results different many times. Sometimes communicate and others not.

I also need good source for a spare key FOB of high quality.

If you respond, please be highly qualified. As I am using my LR for a cross country trip/move.

Thanks.

Steve
As you are planning a long distance trip I strongly recommend you ensure your RR has the correct, larger sized battery. Stealerships and used car lots always put the cheapest battery they can find and even used ones just to get a car off their lot. If the battery is the correct size and at least 800 CCA or more charge it off line, i.e. with the terminals disconnected. While they are, touch and hold them together for 10 - 20 seconds. This will ground and drain lingering bus error codes so that when you reconnect the battery the bus modules will know nothing and have to relearn as you drive. A process that takes about 30 - 50 miles of driving. Corrupted codes get passed around the bus contaminating the logic in modules that shouldn't care. By starting with a blank page and a well charged battery any errors codes will be new and relevant.

After I'd dried out my soaked electronics and installed the LR factory 'plastic mackintosh' over them, a cheap bit of plastic to keep the water leaking in from draining through the GPS DVR, stereo amplifier (Man, you should have heard the loud banging from the speakers the day the rains came in) I'm glad to say everything still worked. I sprayed all the electrical contacts with DeOxit followed by WD40 after it had dried out. Spray all the fuses too. Don't be shy with it. Since I did all the above, and ensure my battery is maintained above 13V, my bus error codes have all gone away.

BTW, the main source for the water that drains down into the left rear corner electronics stack is nearly always the sun roof drains. They become clogged where the pipes come out of the rain accumulation trough. the fronts are easy to clear using a length of Cat 5 network cable. Be gentle to avoid pushing the flexible pipe of the drain spigot defeating the purpose for it's existence. Don't be tempted to use an air gun. That is guaranteed to blow the pipes off. The biggest problem are the two rear drains. It is challenging to access them so they often remain clogged or get pushed off the spigot when someone uses a long stick to rod the drains

Most sunroofs will leak a little which is why they come with drains attached. Water that enters accumulates in the sun roof frame troughs and is supposed to leave via the drains, the front when braking and the rear when accelerating. Mine was so bad that one morning I came out, got in the car and drove off down my street. It had been raining heavily all night but was dry then. As I accelerated I heard water gushing back above the headliner. I pulled over and quickly removed the access panel in the left rear to see water draining down over the LR 'plastic mac' I'd installed.

Our cars are great cars. I still get a lot of admiring comments despite their age. Most people, myself included still think our generation of RR are the best looking they have made to date. So it's worth putting the effort in to keep them running. I'm hoping the guy at Classic RVs in the UK comes through with his planned EV conversion. I'm ready!

Oh, and try to avoid turning on the demister fan, screen heater, seat heater(s), steering wheel heater, heated mirrors, radio, GPS, heated rear window, windsheild wipers front and rear, etc., etc.while the engine is just idling after cranking the engine to life. You would be amazed at how low the available voltage can drop until you get out on the highway. Those poor little can bus modules get starved of juice and their poor little CMOS memories just make mistakes, dropping bits left right and center. And we expect them to never make a mistake while we deprive them of the power then need to get their work done.
 
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