ABS problmes '89 200

[Britt Crowell]

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So the ABS is not working in my '89 200
I've taken out the sensors, cleaned them off and pushed them back in as far as they will go. I can see any damage on them.
I know the guy that used to do the work on the car and he said he though he had replaced them twice already.
How can I test them to see which one is busted, or what other problems should I look for?
If I need to replace 1 or 2 who has the best price or is it a dealer only part?
Thanks
Britt
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