Failure of indicator, tail warning and IPK/speedo back lights
 

Hello all,

My rover 75 has just started exhibiting faults like no back lights behind the speedo, rev counter, clock, also the rear left indicator, front right, both side indicators and dipped beam on one side has all failed. Also the self leveling on the front headlights doesn't seem to be working at all. I picked up new bulbs today and to my horror I found all the filaments were present and no burn/soot marks were present. Am I right thinking that if I change out the LSM circuit board this might rectify this issue or is it something else? I 've check the ECU and its bone dry.

The car has been sitting on the side of the road for three and a half months, due to alternator failure, we have just had a new one installed and the car actually seems to be running better than it was before, but unfortunately this problem started to appear immediately after picking the car up from the garage. The indicator has been a slight issue and when on was fast pulsing about a month ago when we took the car around the block a few times (we did this a few times over the three or so months so nothing could possibly seize up).

I first suspect the LSM, but would it have been possible that if the alternator voltage was not stable (I have had it on diagnostic mode a few times to check the voltage and it was all over the shop, but never went over 14 or so volts), that something else may have been cooked?

I just don't want to order a new LSM and find the problem is still there...

Any help would be appreciated, I know how hard it is to diagnose electrical problems with our cars and I am in no way a expert in car electronics.

Thanks

Don't change the lsm as this stores your mileage & will show "ERR" on the dash & needs a T4 to fix, probably water damage to the lsm. Could be alternator too, I'm sure one of the guru's will be along shortly;):cool:

Hi Stuart,
Check the 2 fuses in the underbonnet fusebox that feed the light switch module (fuse 9E & 11E, both are big 50 amp fuses, of the screw down variety, not the normal blade fuses)
I believe that the way the light switch works is to run about half of the lights off of each fuse (so a single fuse blowing doesn't take out all the lights and leave you unsafe)

Oh, and if you do need to change the light switch, give me a visit and we'll get all your number matching up so there is no err showing on the dash ;)

Regards
Chris

Indicators will flash double time if one of them isn't working - that's true of every car I've ever had (where an indicator has stopped working)

I wasn't aware that the LSM control board had the mileage contained on the board, I thought that the mileage was contained on the IPK; I was thinking about replacing our IPK with the HiLine kit with the computer built into it, and was told back then it needed coding for said reason (mind you it was a long time ago so not 100% sure).

I haven't looked at te cars schematic wiring diagram, but was told that the alternator ran to the battery before running into the ECU..and other computers/digital components, am I wrong to to assume his, and could it have been at all damage due to a faulty regulator, as we got some of these errors, before we got the replacement installed. But mind you the internal lighting is a new issue as well as the headlight levelling.

So I guess I would have to visit my nearest T4 guru to get his sorted out, but I guess I could get further diagnostics done to determine the probable cause of the failure.

We did have some water ingress get inside the car about three years ago due to a smashed window (we got burgled in France), which took a number of weeks to get and install a new second hand spare door and window. The carpets our dry now, and would have thought any damage would have occured back then. I am right thinking that the LSM circuit board is behind the switch pack on the lower right hand side of the steering wheel?

If this is the case I am going to take the switch pack out tomorrow and extract the circuit board box, check the connections for corrosion, get inside it and check the same as well as possibly checking it with the multimeter.

I will add that the indicator issue is mostly intermittent and there is a possibility I suppose for something either shorting out a trace on the board or a dodgy component. The problem definitely seems to get worse after the car warms up and me and my friend suspect its a dodgy component on the LSM board.

I hope this isn't anything major as we have already thrown about £680 at this car in the last 12 months or so and it really is getting to the point that I am getting to the point that these issues are one thing after the other and I am going to unfortunately have to draw the line somewhere!

I think my nearest T4 guy is in Portsmouth, does anybody know of a closer one to Brighton (East Sussex), as logistics with this kind of problem is a utter nightmare and I can't see us driving that distance with such a serious problem; obviously it would also be against basic laws to do such a thing...

I will get back to you peeps in the morning and will post any pictures of what I might find and hopefully can try to find a cheapish solution to this problem (I think we might be able to maybe spend another £100> on it, but if this happens to be a issue with the central computer, I fear it might be going to the scrappers (if it does I will be doing a light strip down before as I might be able to recoup some of the money which has spent on it recently, as it has quite a number of new old stock parts on it now and we have barely done any mileage in the last six or so months as its jst been constant problems one after the other) as I just don't have that kind of money).

Thanks Chris I will do so in the morning when I try doing a bit of diagnostics (or a bit of a poke around with the multimeter...).

Hi Stuart,
If you want to try a 2nd hand light switch, then this will not cause any issues we cannot sort out if you pay a visit.
Just beware, an ordinary T4 cannot deal with 2nd hand light switches, or dashes.
However I can sort these out if you need this service ;)
Regards
Chris

I had problems with the lights that turned to be the module. Well, to be fair to the module it was the sunroof drains not doing their job so rainwater was running down the front offside pillar and getting into the module that has handy vent holes on the top cover. Removing the module and cover revealed a corroded circuit board which was annoying as it was only 18 months old.

I covered up the vent holes with tape and no problems since.

I suppose I should fix the drains...

Have you checked the battery? The first time the tourer showed similar faults they escalated progressively. It was the battery on its last legs - changed it and charged it and the car was fine again.

If the battery is OK and there is no obvious water damage to the LSM itself, my next port of call would be a T4 session. The first question will be whether all the modules are visible on the K bus - it may be that a water-related fault in a different module is interfering with the bus itself. See this thread for similar problems, my tourer suffered faults on indicators, ATC, etc, and it was down to a soggy reverse aid controller.

There have been a number of these water-related issues pop up of late. You say the car has sat for a few months - we've had a lot of rain, and latterly snow, which would test all the known age-related leak points, and not just the plenum drains in front of the windscreen.

Just back to touch base with you guys and gals
 

So the other day my new 2nd hand spare LCM turned up in the post, we promptly went out and changed it, the diagnoses started looking good as the brake lights were working again, but when we went to turn the car off, locked up and walked away all the exterior lights (headlights), were on permanently. We fired her up again, then there were even less lights on than before. The headlights would not turn off, so we put in the old LCM and the cars lights switched off again.

What I hadn't said before is that we have just had a new alternator installed and new Bosch battery installed (which was new from Eurocarparts). The problem started just before the car refused to turn over due to lack of voltage from a dodgy alternator. We had a new "uprated" alternator installed from MAE which was 150 Amp but assured it would fit and work with our car.

Is there a chance that us installing a 150 amp alternator, even though it was recommended for our car, inadvertently fried something? Is there a chance it killed are new LCM, or is there another issue which we don't yet know about.

I am really starting to think we might have to scrap Lucy II, as there is no way I am spending possibly hundreds and hundreds on finding a electronic gremlin which may nOt fix the problem? I just wondered what other people thought?