I think that model uses the ABS speed sensors to determine slippage, which would cause the ASR light to come on, so it seems that you are on the right track, however I would be unsure of throwing so many parts at it. I have had several 129's and never had a speed sensor go bad. Also have you replaced your engine wiring harness? That model if not changed needs to be, and if not it can really goof things up, a friend didn't replace his and it blew both the engine computers on his 600. Another cause of the ASR light is the ETA, those can cause the malfunction as well. As you know the ETA controls the throttle during slippage and if manlunctioning it will cause the light to come on. As for the ABS problem, that could be related, however I would start with the harness if not already replaced. If you have replaced it, then go for the master cylinder, but I have never had one of those go bad either, except I have seen them go when friends use those pressure bleeders on them. Do you change your fluid regularly? Go from there. Good luck!
Brian

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Brian W. Heitman

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