2006 RR HSE 4.4 gas
A few months ago I changed the transmission fluid. Everything went smoothly, test drove it after for 60 miles and it was shifting flawlessly, no codes, no issues. Next morning, would not start. Battery was a bit weak and old so replaced. Still no start. Had a shop replace starter. It began to start, but now I suspect it was only because they cleared the codes.

Drove fine for a couple days, then about 0.5 miles after cold start one morning, threw me out of gear with a bang, transmission fault - limited gears available, HDC fault, etc. etc. on the dash. CEL comes on. Won't go out of 3rd gear. Pull over, cycle the ignition and the messages go away and it drives fine.

Continues doing this on and off. All codes relate to communication failure with transmission control module. Sometimes will not start. Only way to make it start is clear all the codes. Took it to a specialty shop, they say nothing is wrong with it. Relearned the transmission with GAP tool, no change.

I'm going to try replacing the ignition switch, and if that doesn't work, perhaps the alternator? I'm at a loss. Shop time is very expensive and seems to be totally useless. When the car is driving there is clearly nothing wrong with the tranny, shifts fine through all gears and gets good gas mileage. Smooth as can be.

Went through live data, everything seemed normal except transmission power supply voltage, which read as 7.0V with engine on and off. Is that correct?

Any ideas or advice? Below are some of the codes I'm getting:



Model L322 - Range Rover 2006
Vehicle scanned on Jan 16, 2023 6:18:34 PM
IIDControl 3.0.4 Build 90 Android - IIDTool BT V4.0 B2803

HVAC-Heat / Cool

0x30 Air quality sensor line fault

IPC-Instrument Pack

U0248-87 (2F) Lost communication with remote driver utility module - Bus signal/message failure - missing a message
( on 16-01-2023 16:36:47 at 149181 mi )

LCM-Light Control

0x7B Front right sidelight defective

PAM-Parking Aid

0x5 Front left ultrasonic sensor

0x6 Front right ultrasonic sensor

PCM-Engine Petrol

U0101-00 (A Lost communication with transmission control module

TCCM-Transfer Case

U0101-87 (2C) Lost communication with transmission control module - Bus signal/message failure - missing a message
( on 15-01-2023 17:59:31 at 149151 mi )

VDM-Vehicle Dynamic

U0101-87 (0 Lost communication with transmission control module - Bus signal/message failure - missing a message
( on 15-01-2023 17:59:59 at 149151 mi ) 2006 HSE 4.4 gasser

Currently ripping apart the center console to get to the ignition switch... surely these splices are not factory? There doesn't appear to be anything aftermarket in the car so I'm very confused why these would be here. Perhaps I'll find out once I get it more open.


 2006 HSE 4.4 gasser

Seems to be the transmission electrical connector is the issue. I replaced the sleeve that goes into it per the atlantic british instructions during the transmission service, and somehow it did not go in right, even though everything locked together.

Today I removed the electrical connector, blew it out with cleaner, plugged it back in, and it's running again with no faults. I guess ZF fluid conducts electricity? I will have to do another transmission service to fix the leaking sleeve but until then I guess I can just clean it out periodically. 2006 HSE 4.4 gasser

We had most of those codes come up on the GAP. Took it over to Bristol Gearbox, they carried out an electrical test (passed) and now they are saying a strip down of the mechatronic unit and needs a full transmission overhaul. £2650 + vat + anything else they find. We are wondering if it’s worth doing, over 200000 on the clock. Thing is we have spent a fortune the last year, new PIR tyres, brakes, discs, full service with all filters, gearbox pan change with service…..the list goes on and on

That sucks... I wonder if you could do the teardown yourself and just bring in the unit to the shop so they can do whatever computer wizardry they need to, then finish up the service yourself. Getting the unit out and replacing solenoids isn't hard at all.

See this video:  2006 HSE 4.4 gasser

We wish we could, arthritis stops a lot of things. We can only check things, any repairs, it goes to the garage.
Excellent vid by the way. 1983 Range Rover Classic red CHP 723Y
H81 MFX Classic
1995 P38 4.6 HSE
2006 L322 V8 Vogue supercharged

If it's been a good car and this is the only issue, I would spring for the tranny rebuild. If you junk it you'll have to buy something else, and that's going to cost even more, and could come with issues of its own. 2006 HSE 4.4 gasser