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Discussion Starter #1
Top won't work after a replacement of all hydraulic cylinders. Indy took it to MB for code reset and worked fine. Then dealer drove and top wouldn't work. Reported fault with ABS code causing top to stop as it thinks car is in motion. Said need new ABS Control Module. Car has ASR as well. Question is I cannot find any place on line that has a unit where the Bosch # matches the one in the car? Part number in unit in car is 0075454232 unless we read it wrong in a hurry today. Rock Auto for example lists two reman units for this year and model (I assume one for with ASR one for W/O) but neither part number matches? Anyone shed some light on this?

Also, what else could cause this other than a bad ABS CM?
 

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Don't always be quick to take the dealer recommendation....there could be a way cheaper fix....give the others who have been there done that a chance to respond.

hope it is simple
 

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Zachmac hello and welcome in our big and international friendly family:). Please update your profile with your car, year and location to help us help you in the best and quickest possible way. For us it’s extremely important you do this.

Please get familiar with the Advanced Search feature of the forum as the matter as been discussed already.

Anyway, tommygunns1992 is right spot on. I mean that most likely it's the speed sensor that needs a nice cleaning causing your top to get stuck since the soft top control module gets the speed signals from the ABS sensors to allow or deny soft top operations.

Hope it helps for now.

Cheers.
 

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Discussion Starter #6
Update; after cleaning and testing all four sensors (yes 4, ABS and ASR) they all show good. Installed new ABS / ASR control module (known goiod unit) and no change. Also tried swapping instrument cluster with known good one, no change.

Symptoms are no warning lights following any restart, roll the car ten feet and ABS light comes on. ASR light doesn't come on. Also no cruise control and snow chain button (assume it is ASR bypass?) doesn't light up if do anything.

I've read a lot of the stickies and threads at this point. Any common cause for this set of symptoms?
 

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LOOK UP "CODE READER" IN SEARCH AND LOCATE DIAGNOSTIC PORT. GET THE CODES AND SEE IF ANYTHING POPS UP THERE....NOT SURE WHICH ONE YOU HAVE ALTHOUGH I WOULD GUESS 16 PIN OR 9-10 PIN. MINES ON THE RIGHT SIDE IN FRONT OF THE CONTROL MODULES.
 

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Discussion Starter #8
Update

Update: Thanks to all for pointing to the right threads and stickys. I am still chasing this one down and have now basically resorted to a pin by pin trace of all sensors, inputs and wires. I agree that it sure seems like it should be a sensor problem but they all check out fine with no codes, continuity and proper resistance readings and volts generation with tire rotation.

Tommygunns1992: I did indeed make a trip to radio shack and assembled a rudimentary code reader. Went whole hog and spent the extra $6 for the little balck box to hold it all!:) My car is a 16 pin diagnostic port. Got all the wiring diagrams and code charts so it should just be a matter of putting in the time to trace the problem.

BTW is has been suggested that I also check tire / wheel size as non-OEM rolling radii can throw off ABS. However the car is sitting on the same OEM rims and tire sizes that it has run with for 11 years with no ABS issues.
 

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Discussion Starter #9
....abs mod is around 800 and speed sensor could be cleaned and it is 200-250. might be worth a look see...
Tommygunns: Do you know of a source for this control unit? Most everyone selling reman or used ones has them for non-ASR cars but very hard to find anyone with an 0075454232 which is apparently unique to the ASR six cylinder cars. Everyone who has them new / NOS wants $1800 or more and the Stearlerships quote $2600!!!! I sourced one used one off sleezbay that claimed to be good for $150 (seemed like it was worth a shot at that price) but swapping it out made no difference.

I'm not convinced at all the CU is the problem but wanted to have a source if it turns out to be it.
 

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Zachmac, I had an ABS light issue for a long time. Checked all sensors.....etc. no luck. Had a low brake pedal, so replaced rotors and pads. Still had low pedal and ABS light. Flushed brake fluid and bleed lines, ABS light is OFF!!! and pedal is up. In my case, most likely had air in system, although needing brake pads as well. Good luck, victor62
 

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Discussion Starter #11
Zachmac, I had an ABS light issue for a long time. Checked all sensors.....etc. no luck. Had a low brake pedal, so replaced rotors and pads. Still had low pedal and ABS light. Flushed brake fluid and bleed lines, ABS light is OFF!!! and pedal is up. In my case, most likely had air in system, although needing brake pads as well. Good luck, victor62
Victor,

Thanks for the insight. It sounds like it is worth a shot if nothing else shows up soon.
 

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Discussion Starter #12
It is fixed!!!!

ABS fault was due to bad wiring harness between front left sensor and rest of car! Replaced it and no ABS light and top works like a champ. Thanks to all for the advise and assist. The cruise is the only thing still not working so I'll get hot reading all those old posts next.
 
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