Had the same problem some time back (have 2003 TD5 auto), manual says that when M & S lights flash together then car will go into "limp home" mode, this is SO TRUE, just plugs along in 3rd, great when you are towing a caravan and have nowhere to stop. Anyway, it got so that the lights came on every time I backed out of the garage and I had to stop, extract key, lock car, unlock car, insert key, restart car but avoid reverse like it was a snake, then whoopee away we went.
Finally had to get the LR gurus to check the fault codes during next service, they reported that it was the auto gearbox Inhibitor switch(P/N in Aus ROUHB100190, price in Aus $414.58) problem has not reappeared since new part installed.