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Caesar
New Member
- Joined
- Dec 17, 2013
- Messages
- 22
- Reaction score
- 0
- Points
- 0
- Location
- RI
- Vehicle Year
- 1998
- Make / Model
- Mazda
- Transmission
- Automatic
The speedo (which is off by between 3-5 mph) in my 98 Mazda B4000 temporarily decreases in speed when I tap the brakes, touch the power windows, or use the turn signals. It only does it for a split second and then it goes back to the normal speed. When using the turn signals it pulsates or ticks back and forth. It only happens when going over 40-50 mph and it doesn't do it while the headlights are on. It does tick when I turn the headlights on, but after they are on it behaves normally. It seems to occur when there is a sudden spike in amperage and then it stops. The drop in speed doesn't seem to effect the shifting, although it is only for a split second here and there.
Could this be an issue inside the GEM module? I know the speed signal goes from the rear axle to the GEM and then branches out to the rear abs module, the dash, the ECU, and cruise. Or could there be a short between the GEM and the cluster? What should I zero in on or what area should I focus on to get to the root of this issue?
Could this be an issue inside the GEM module? I know the speed signal goes from the rear axle to the GEM and then branches out to the rear abs module, the dash, the ECU, and cruise. Or could there be a short between the GEM and the cluster? What should I zero in on or what area should I focus on to get to the root of this issue?
