False brake light fail indication by SAUNDERS

On my 2.5ConnoisseurSe Hiline a false indication of LH brake light failure has appeared and cannot be cancelled. Bulb and wiring are intact so problem is likely to be in the LSM (Light Switch Module). Relevant fuses 9.11,13,25 wer removed overnight hoping for a general reset but no change. I understand that the LSM also holds mileage and VIN (Vehicle Identification Number) data and must be rocoded using T4 (Testbook version 4.Computer Diagnostic System) if changed and furthermore S/H LSMs cannot be recoded. There seem to be two (or more) types of LSM YW2000 200 and 201. What is the difference? Mine has a thumbwheel for headlamp levelling - others do not. Can the front panel be changed and added to the rest of the module if the new module does not have the thumbwheel and will it then work? Are new modules with thumbwheel available anywhere? Any comments and advice, particularly if the is an alternative solution to this problem will be gratefully received. Thanks.

Posted 11 Feb 2013, 15:07 #1 

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I've never heard of a failed one, though it could happen. You could try a second hand one to prove it out, but there would be a mileage mismatch. It would prove the point, though.

I think it's now possible for some people to reset the memories on LSMs to as new, David (Monk) might be able to comment.

Posted 11 Feb 2013, 21:01 #2 

2nd hand LSMs can be recoded. Do you have a part number for the one in your car as I have a couple here but not sure what state they are in :???:

Posted 11 Feb 2013, 23:32 #3 

Many thanks for your response. I will try to find the part number next week and will communicate via PM wen I find out how to do that !. Best regards, Saunders

Posted 12 Feb 2013, 12:41 #4 

Regarding false brake light filure indication i forgot to mention that the LH bulb does not light but it and wiring qare intact.

Posted 12 Feb 2013, 15:06 #5 

Problem solved! I removed the LSM and checked fr continuity between pin 5 of LSM connector and Stop light. A previous owner had fitted a towbar with rather untidy wiring using Scotchloks and I eventually found that the stop light wire had parted as it left the scotchlok although visually it looked fine. Tidying this up made everything work properly so thanks for all the advice and offers of help. By the way, the part number of the LSM of my car (registered 31/3/2005 - the day before Rover went into administration!) was YWC 106950.
I shall be removing the towbar and its electrics soon so if anyone wants one please contact me.

Posted 21 Feb 2013, 17:56 #6