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I’ve got a 2004 Santa Fe 2.7L engine 6 cyl. Engine. 157k Miles.

The speedometer bounces up and down when I drive at any speed. All other instruments seem to be working fine - tachometer is nice and steady but it does bounce when I engage the cruise control. No check engine light and no ABS light.

Because there’s no engine light the mechanic told me to keep driving until a trouble code shows up so that he can pinpoint the problem but I most definitely don’t want to do that. He says it could be the speed sensor or the cluster.

Is there an easy test to figure out which part is faulty? Any other info that would be useful also appreciated.
 

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Scanner and read the VSS signal while driving. It would be spiking. I would guess it is the speed sensor in the tranny. The VSS( mechanical spinning sensor with the gear in the back of the tranny)
 

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Drives : Nissan NV200 Flies : Rans S6ES
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Scanner test wont really help. The scan tool reads the vehicle speed from the engine PCM and the engine PCM gets it's speed data from a totally different sensor to the instrument cluster.

As chris6414 says, the instrument cluster VSS is mounted on the gearbox and is driven by a plastic gear. Sometimes the sensor drive gear gets damaged, causing the speedo needle to bounce. I'd suggest removing the sensor and checking the drive gear. I'm pretty sure the gear is available as a separate part if you find a problem with it.



 

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I should have said a "good" scanner. Mine will actually read the VSS signal.
So my speedometer isn't working at all now can I get some advice?
I used an obd2 scanner on my car and it was reading the speed of the car but the speedometer, (miles on car) odemiter, and cruise control isn't working and all fuses are good. I am at a loss of what to do
 

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I am at a loss of what to do
The first thing you should do is locate the speed sensor on the gearbox (usually right back at the firewall/bulkhead) and check the voltages on the terminals of the sensor's harness connector. There should be one with 12V (power supply), one with about 11V (signal), and one with 0V (ground). If the power supply & signal voltage are good you next need to test the ground by connecting you voltmeter between battery positive and the terminal that showed 0V in the previous test. If the ground is good you should now have 12V on the meter display. If all three voltages are correct I think it's safe to assume the sensor has failed.


If I helped you fix it, why not...

Your support is greatly appreciated
 
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