Electrical Faults.

Aerosteve · 2nd February 2020, 12:27

Mysterious electrical faults have appeared since the car was unused for a couple of weeks, my battery went flat, and I charged it. Car will start OK.

Indicators and hazards work but no warning lights on dash;
Car wont lock with key but can be locked/unlocked with switch in car. Changed key battery;
Radio/computer screen is blank but I can hear clicks from speakers.

Any ideas?

Mike Noc · 2nd February 2020, 12:45

Likely a fault on the K bus, which is one of the communication links for some of the ECU's.

Try this test: With the ignition switch at pos 2 and drivers door open, if message centre is fitted the "door open icon" should be showing if the BCU K Bus is good.

And if you have a factory fit Satnav, check the plug connections haven't got wet and corroded.

.

BigRuss · 2nd February 2020, 15:31

If your car has highline satnav, then it's most likely to be faulty video module, it's the one on the left under the black plastic cover in the spare wheel well.

Disconnect the blue and white plugs and see if the indicators and door locks regains normal function.
If it does then you'll need a good replacement so that you regain full functionality of the Audio system and satnav.

Russ

trikey · 2nd February 2020, 16:42

Or if you have a sunroof, check the immobiliser for signs of dampness.

Aerosteve · 3rd February 2020, 12:56

Thanks Gents.

I removed the blue and white plugs in the spare wheel well and indicators and central locking working again. There was a pool of water in there so investigating where its getting in. Car is a tourer incidentally. Trying to dry the two boxes in there with fan heater at the moment.

2nd February 2020, 12:27	#1
Aerosteve Newbie Rover 75 Tourer Join Date: Aug 2012 Location: Isle of Man Posts: 17 Thanks: 0 Thanked 2 Times in 1 Post	Electrical Faults. Mysterious electrical faults have appeared since the car was unused for a couple of weeks, my battery went flat, and I charged it. Car will start OK. Indicators and hazards work but no warning lights on dash; Car wont lock with key but can be locked/unlocked with switch in car. Changed key battery; Radio/computer screen is blank but I can hear clicks from speakers. Any ideas?

2nd February 2020, 12:45	#2
Mike Noc This is my second home Rover 75 CDT Manual Connoisseur SE, Rover 75 CDT Automatic Connoisseur SE & a Freelander Td4. Join Date: Jul 2009 Location: Hampshire Posts: 11,551 Thanks: 3,470 Thanked 3,119 Times in 2,247 Posts	Likely a fault on the K bus, which is one of the communication links for some of the ECU's. Try this test: With the ignition switch at pos 2 and drivers door open, if message centre is fitted the "door open icon" should be showing if the BCU K Bus is good. And if you have a factory fit Satnav, check the plug connections haven't got wet and corroded. . Last edited by Mike Noc; 2nd February 2020 at 13:38..

2nd February 2020, 15:31	#3
BigRuss Premium Trader 75 CDT Tourer,2.5 Launch Saloon, Omipro MG/Rover (T4) Join Date: Jul 2007 Location: Liversedge, West Yorkshire Posts: 5,405 Thanks: 1,105 Thanked 1,340 Times in 661 Posts	If your car has highline satnav, then it's most likely to be faulty video module, it's the one on the left under the black plastic cover in the spare wheel well. Disconnect the blue and white plugs and see if the indicators and door locks regains normal function. If it does then you'll need a good replacement so that you regain full functionality of the Audio system and satnav. Russ __________________ Replacement Key Service http://https://the75andztclub.co.uk/...d.php?t=244732 Full T4 Testbook diagnostics available. Diesel ECU repair and replacement. Options enabled or disabled as required. Diesel X-Power 135 and 160bhp, Rover 1.8T 150 to 160 MG 160 V6 to 177 upgrades available P.M. for details.

2nd February 2020, 16:42	#4
trikey Premium Trader Rover 75 Join Date: Nov 2010 Location: Devon Posts: 33,776 Thanks: 8,837 Thanked 14,831 Times in 8,030 Posts	Or if you have a sunroof, check the immobiliser for signs of dampness. __________________ Lest we forget..

3rd February 2020, 12:56	#5
Aerosteve Newbie Rover 75 Tourer Join Date: Aug 2012 Location: Isle of Man Posts: 17 Thanks: 0 Thanked 2 Times in 1 Post	Thanks Gents. I removed the blue and white plugs in the spare wheel well and indicators and central locking working again. There was a pool of water in there so investigating where its getting in. Car is a tourer incidentally. Trying to dry the two boxes in there with fan heater at the moment.