# 2009 Murano speed sensors work but computer says 0km/h



## Murano 2009 (Apr 28, 2021)

My 2009 Murano's abs and traction control light came on. 

I ran a test on the computer to check the speed sensors and the front left sensor wasn't detecting any speed.

So I switched around the front sensors, and put it back on the computer. I got the same code for the same side (front left bad). This means that the sensors are good. 

Just to be sure, I took a magnet and quickly moved it back on forth on both sensors. The computer had a reading. 

I unplugged both sensors and checked if there was a current in the plug. There was current, around 12 v on both sides. 

I used my sand paper and then a hose to clean near the hub incase there may have been something that is throwing off the magnetic field.

Still no reading on the front left speed sensor.

One more thing to note, I'm not sure if this started at the same time. But when I step in (or out ? )Of the Murano I get a little shock.

I tried my best to trace the right wire back as far as I could to see if there was any damage. Didn't see any. The left sensor quickly goes in to the flex tube with the rest of the wires. But again, both speed sensors were giving a voltage around 12 v. 

I find it hard to believe the magnetic ring in the bearing could get demagnetized. 

I'm not even 100% sure if the ring is part of the bearing, a seperate piece from the bearing, part of the drive shaft. Any advice would be appreciated.


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## VStar650CL (Nov 12, 2020)

First off, did you erase the codes in the ABS before driving it with the sensors swapped, and did you drive it for a ways? Very often sensors start to "glitch" and it may take some time and miles for the code to recur. If you erased it and the error recurred immediately, that's different, it means something is open-circuit. If it's intermittent, check your wheel bearing on the bad wheel, a deteriorating bearing changes the distance between the sensor and reluctor and can cause come-and-go codes. If it recurs immediately, you'll need to break out the wiring diagram and ohm between the sensor and the ABS. One thing I'll point out is that rodents love to chew the front sensor wires where they enter the engine box, usually on the righthand side beneath the wheel well liner but sometimes on the left under or around the IPDM. If your ohmmeter finds broken wires but you can't locate the break, there's nothing wrong with running replacement wires on the outside of the harness. However, do it correctly without shortcuts. Replace _both_ wires even if one is good, use solder-shrink type connectors _only_, and run the new wires in a twisted-pair just like the originals. No need to buy twisted pair, you can use a power drill to twist ordinary hookup wire of the appropriate gauge.


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## Murano 2009 (Apr 28, 2021)

Thanks for all these details, very helpful info indeed. I'm actually not 100% sure if we did a reset. I'll try to get my hands on the computer if I can. 

Just to be clear, we didn't use a typical 50$ or 100$ scanner. 
We could see LIVE data of the speed on each wheel as we drove. Since the data was live and changing while we accelerated and slowed down, I assumed there was no need to reset anything. If the data is live, do I still have to reset?

It gives 0 kms right away, so not intermittent (but this might be because we didn't reset it)

I checked the wires as far back as I could for both the front ones, even took some of the wire out of the "tape" they look ok. 

Despite not doing a reset, I have to mention that when we switched the sensor (not resetting it) both sensors, when placed on the passenger side gave a reading. Wouldn't this be enough to rule out the sensor? If so, we are left with the drivers side bearing or the circuit it self. 
Since the wires look good, wouldn't it be safe to assume it's the bearing/reluctor?


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## Murano 2009 (Apr 28, 2021)

If both sensors are good Soni still have to do a ohms test? 
Does the ohms check verify the circuit or the sensor (I know the sensor is good already as both gave a reading on the passenger side ) ?

Any idea what ohms values are acceptable ? 
_-------------------

Also, of I recall correctly , when. I tested the good side I tried once with sensor pulled out just to see. Naturally it gave a reading of 0, when I put the sensor back in, it began to read the speed again. This indicates that there is no reset needed.


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## VStar650CL (Nov 12, 2020)

Murano 2009 said:


> We could see LIVE data of the speed on each wheel as we drove. Since the data was live and changing while we accelerated and slowed down, I assumed there was no need to reset anything. If the data is live, do I still have to reset?


Watching the live stream doesn't tell you whether the ABS is ignoring the sensor because it glitched out and now it isn't trustworthy. Many DTC's are like that, the ECU will ignore the subsystem until it passes enough self-tests for the DTC to go "past" instead of "current". So yes, it matters whether you cleared it. Since you get readings off both wheels, it's almost certainly a glitch that's happening once in awhile and probably too fast to see without a scope. ABS's are generally very particular about wheel sensor signals, they expect to see every tick on every rotation without fail. Glitches won't show up in streaming speed data but they will generate a code, usually instantly. Your most likely culprits are the wheel bearing or high-resistance / bad pin-fit in one of the two circuits. Note that if it's the bearing, the code is most likely to pop up during a turn, and usually in the same direction every time. If it's wiring or pin-fit, you simply won't find it without the WD, a pin-fit tool, and an ohmmeter. You're looking at a high-resistance condition, not an open circuit.


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## Murano 2009 (Apr 28, 2021)

Ok, I'll try it out tomorrow. It's starting to get a bit over my head but I'll have some help.


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## Murano 2009 (Apr 28, 2021)

The bearing that wasn't reading all of.a sudden Got really bad, so bad I was scared.to drive it. So I changed the bearing. I made sure to double check that the new bearing had a magnetic ring. 

After I replaced I was expecting the abs AWD light to go away. It didn't. 

I used a computer to reset the code( a 1000$ plus.computer.) 
The lights wouldn't go away. Even when the car was stopped and i did a reset, didn't turn the wheels(so there was no way for the speed sensor to know if it was good or not) the light didn't flinch! 

To recap
1. Left side speed read 0 kms all the time 
2. Right side reads correct km/hr 
3. When right and left sensors are switched, still it says left is 0km/hr and right says correct speed indicating the sensor is ok.
4. Wires seem all good all the way in.
5. Changing the bearing didn't help (still detects 0km/hr)
6. Both sides read a volt around 12 v in the wires. 
7. Abs AWD break light didn't go away when reset.

I am leaving the battery unplugged over night to make sure the reset is done. But either way the live data should.of caught the speed as it's live


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## VStar650CL (Nov 12, 2020)

Murano 2009 said:


> 4. Wires seem all good all the way in.


"Seems" won't get you there, either break out an ohmmeter or jump out the wire pair. It's clear you have a wiring or pin-fit issue that you won't _ever_ find by eyesight.


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## Murano 2009 (Apr 28, 2021)

I'll check that out


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