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Discussion Starter #1
Hello all, I am working on a project 2001 M5 and am getting 6F and 70 BMW codes from my Foxwell scanner. Codes are "Pedal-travel sensor comparison fault" Searching for those codes, 99% of the time, I am directed to TPS related threads but this is not TPS, it is PTS! Unlike other E39s that have an integrated accelerator, the pedal travel sensor in an M5 is a drum shaped lever a bove the pedal connected by a link. I have another E39 M5 but am not in a hurry to canibalize it for testing on the project car. They are rather expensive parts, so I am curious if anyone has any recommendations on testing it. Any suggestions?
 

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I think you can test it with a multimeter but I'm not familiar with the details of which pins to check, etc. If you don't want to replace it with the same type of sensor, you can actually retrofit the newer style pedal with the integrated sensor. I just did this on my car recently. The cost is nearly half that of the old style sensor. I will be posting a DIY for this soon, but here's my thread discussing it.

 

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You say it is not TPS, but why? Because your scanner says something in the words that are confusing you? Both your codes are comparison faults and the pedal pot is a single signal split by the DME and two signals are sent to the TPS.
I would check the TPS signals with a pair of volt meters at the same time. they add up to ~5 v but whatever the voltage 5.3 say they must always add up to the same within 0.1 v IIRC. Do a full sweep of the pedal looking for any drops or rises. They are much easier to test.
 

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Discussion Starter #4
Very good info. Your other thread is interesting. As a current owner of 5 M5s and prior owner of several M3s, I can tell you that BMW rarely updated M vehicles when they updated the production cars. A good example is the E46 headlight surrounds and other post-facelift items, which were never facelifted on the E46 M3. As far as I can tell, the only time they changed M designs during a run is when something was defective (like early E34 door cards) or when emissions or some other regulatation required it. (E39 Hella headlights are a notable exception...but the rubber trim strips on the E39 M5 never changed to post-facelift body color....) So it makes perfect sense that they would continue to use the old 2-sensor design on the M5 rather than the newer integrated 540i design.

About your other thread. The long to realoem no longer works. Can you please tell me what accelerator you used? I'm assuming it is the late model 540i accelerator since it is more likely to have 2 separate sensors. I have a couple of late 535is with the late accelerators, but I'm guessing those are single channel.

Now, that said, I'm not entirely sure that the issue is a bad PTS and I'm not sure it is a good idea to swap accelerators before the source of the code/limp issue has been identified. The project car I'm working on has something called a WOTbox, which is a launch control and shift point manager. It was not designed for BMWs but it has been wired into the car somehow. I have not yet had a chance to see where. I know that a wire or two had to be spliced for it to work and I suspect that the WOTbox was not designed for 2 throttle bodies, meaning they might be wired together.

So, since I did not get anyone with the magic-bullet soltution I was hoping for, I'm going to have to go about this systematically.
1) Remove the WOTbox and splice any wires that were altered to control it.
2) test. If this resolves the issue, done.
3) If not, pull thee connectors on the project e39 and test the resistance of the two channels to see if they match.
4) Possibly pull the connectors on my good M5 to see if the number differ from the project car.

Can you think of anything else?
 

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If you're going to go to the trouble of testing the sensors on the engine, just replace them with new OE sensors. Trust me, you don't want to remove and install them more than once. It sucks. The pedal pot is a lot easier to test, as Sailor mentioned, but you will need to drop the lower dash panel under the steering column to get to it.

The updated pedal/sensor that I used is part number 35426786282. It has a built in hall effects type sensor rather than a potentiometer type like the old sensor.
 

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Discussion Starter #6 (Edited)
You say it is not TPS, but why? Because your scanner says something in the words that are confusing you? Both your codes are comparison faults and the pedal pot is a single signal split by the DME and two signals are sent to the TPS.
I would check the TPS signals with a pair of volt meters at the same time. they add up to ~5 v but whatever the voltage 5.3 say they must always add up to the same within 0.1 v IIRC. Do a full sweep of the pedal looking for any drops or rises. They are much easier to test.
I'm not confused at all. (nice passive/aggressive response, too, dude.) I am getting a PEDAL travel sensor error, not a THROTTLE position sensor error. I always though that one reason the M5 FBW system never changed was because it had 2 pedal sensors. No? Are you sure? If it is a single signal from the accelerator, why is my BMW-specific code saying that the PEDAL is generating a mismatch errors? (BMW codes 6F, 70) BMW has separate codes for PTS and TPS mismatch faults. Why would that be if the pedal is single channel? I understand exactly what you are saying, but I also understand that my Foxwell scanner (and probably my old Peake and my Reingold Ista-D and my DIS) is telling me it is not TPS, but the accelerator. Now, I outlined a different plan of action elsewhere in this thread because some asshat PO installed a WOTbox. Apparently he had it working but I have no need for it as the drivetrain for this caar is going into an E39t. Once I get that WOTbox removed and sorted out, I'll address again whether it is PTS or TPS, pulling the POT from my other E39 M5 if I have to. Again, are you SURE the accelerator is single channel? Can anyone confirm?
 

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Discussion Starter #7
If you're going to go to the trouble of testing the sensors on the engine, just replace them with new OE sensors. Trust me, you don't want to remove and install them more than once. It sucks. The pedal pot is a lot easier to test, as Sailor mentioned, but you will need to drop the lower dash panel under the steering column to get to it.

The updated pedal/sensor that I used is part number 35426786282. It has a built in hall effects type sensor rather than a potentiometer type like the old sensor.
My objective is to avoid replacing the sensors on the engine at this time as this is a donor car for an M5t project and at least a partial rebuild will be done while it is between cars. I've been operating under the assumption that the M5 accelerator is dual channel. When you swapped for the 6282 sensor (which I looked up on realoem and is the universal accelerator for both the 525i and 540i) is it a single channel or is it dual channel?
 

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The pedal sensor IS dual channel - that’s how the DME detects a fault and has a fail safe.



You could also test it at the DME which will also test the wiring.




Having said that, I’ve been repairing BMW’s for a year or so and it’s been my experience that most faults (particularly electrical) are caused by aftermarket equipment or an outside influence (e.g. water ingress).
So, as you’ve already suggested, first step would be to remove that WOT box and correct the cars original wiring - pay particular attention if “scotch locks” have been used on the wiring to fit it because they cut through the wiring and can cause high resistance.
 

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You say it is not TPS, but why? Because your scanner says something in the words that are confusing you? Both your codes are comparison faults and the pedal pot is a single signal split by the DME and two signals are sent to the TPS.
I would check the TPS signals with a pair of volt meters at the same time. they add up to ~5 v but whatever the voltage 5.3 say they must always add up to the same within 0.1 v IIRC. Do a full sweep of the pedal looking for any drops or rises. They are much easier to test.
6F and 70 are definitely for the pedal sensors. The DME receives two voltages from the pedal. The primary is scaled from ~0.5-4.5v, and the second should always be exactly half that of the primary.
 

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The pedal sensor IS dual channel - that’s how the DME detects a fault and has a fail safe.
Is that why the % throttle readout in INPA, Torque, etc. always looks a little weird? Does it only read one channel or something?
 

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Is that why the % throttle readout in INPA, Torque, etc. always looks a little weird? Does it only read one channel or something?
throttle / torque will not always be correlated with pedal position. Inpa only shows the value of the main pedal sensor if I remember correctly, but both voltages are output in the diagnostic message.
 
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