# Mazda B4000 warning lights on/speedometer out

**URL:** <https://community.cartalk.com/t/mazda-b4000-warning-lights-on-speedometer-out/52708>\
**Category:** Maintenance/Repairs\
**Tags:** b4000, mazda\
**Created:** [July 30, 2010, 6:19pm UTC](https://community.cartalk.com/t/mazda-b4000-warning-lights-on-speedometer-out/52708 "2010-07-30T18:19:45Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![agberg](https://avatars.discourse-cdn.com/v4/letter/a/ebca7d/32.png) [@agberg](https://community.cartalk.com/u/agberg)\
**Post date:** [July 30, 2010, 6:19pm UTC](https://community.cartalk.com/t/mazda-b4000-warning-lights-on-speedometer-out/52708/1 "2010-07-30T18:19:45Z")

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Hi…  
  
  
  
 I’ve got a 2000 Mazda B4000 truck…98K miles and running fine. But the ABS and Check Engine warning lights are on, and the speedometer isn’t working. Does this sound like a “minor” electrical problem or something more serious? Thanks.

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**Author:** ![researcher](https://avatars.discourse-cdn.com/v4/letter/r/edb3f5/32.png) [@researcher](https://community.cartalk.com/u/researcher)\
**Post date:** [July 30, 2010, 6:51pm UTC](https://community.cartalk.com/t/mazda-b4000-warning-lights-on-speedometer-out/52708/2 "2010-07-30T18:51:25Z")

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There is an Output Shaft Speed sensor attached to the rear of the transmission. This is the first thing I would look at to troubleshoot the symptoms you describe.

Hope this helps.

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**Author:** ![Dan\_Smithers](https://avatars.discourse-cdn.com/v4/letter/d/858c86/32.png) [@Dan\_Smithers](https://community.cartalk.com/u/Dan_Smithers)\
**Post date:** [August 19, 2010, 3:33pm UTC](https://community.cartalk.com/t/mazda-b4000-warning-lights-on-speedometer-out/52708/3 "2010-08-19T15:33:29Z")

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Hi agberg – We are having exactly the same problems with our Mazda B4000 – Would sure appreciate hearing what the problem and fix was in your case. Thanks!