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Discussion Starter #1
Does anyone know what this code actually means?


  • 2A - Vehicle speed input signal, hardwired ‘A’ signal

I searched around on the board and keep finding it in various posts about the various codes from the peake code reader but have yet to find a post where someone else has actually had the code.
 

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Are you sure you have the right table? In table 1b...code 2A is vehicle speed sensor.
 

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Discussion Starter #4 (Edited)
Are you sure you have the right table? In table 1b...code 2A is vehicle speed sensor.
Yes, the manual I have for the R5/FCX-3 reader is (Rev. 1.1 NA) and shows Table 18 & 1b together, and 2A is Vehicle speed input signal, hardwired "A" signal; however, according to this thread, http://www.m5board.com/vbulletin/e3.../99962-knowledge-base-peake-codes-e39-m5.html, the manual shows Table 1b separate with code 2A as Vehicle speed sensor.

I'm assuming its the speed sensor but was unsure.

The better question here is why are there 2 different manuals for the same reader?
 

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Discussion Starter #5
What are the symptoms?

The only symptom I can think of is the "TIRECONTROL INACTIVE" message I keep getting. Because I also have the ABS module issue, I just assumed the message had something to do with that. Other than that, the SEL light popped on, i read the codes, and got 2A.
 

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Is there a chance this is an old code? Sorry you had an ABS issue?(I will search) When do you get the tire inactive? If you put the key to position 2 and push the RDW button does anything happen? Does it give you the set up message or just nothing?
 

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Discussion Starter #7
Is there a chance this is an old code? Sorry you had an ABS issue?(I will search) When do you get the tire inactive? If you put the key to position 2 and push the RDW button does anything happen? Does it give you the set up message or just nothing?
No, this is not an old code; I've cleared itand it has came back. I get the tire inactive after driving for a few mins. My research here on the board suggests that this could be due to a wheel speed sensor. I wonder if the 2A code is causing this issue. What is the RDW btn? I assume you talking about the btn to the right of the steering wheel?
 

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Yes that button. I am not sure about the system. Don't think mine works at all. I get no message unless I push the button twice which turns it off. When my ABS/dsc was not working I got the inactive message. I am at a stand still with mine.

The 2a is a wheel sensor code I have heard it referred to with DSC and ABS. I don't think it is a specific one though. I think it means the sensors don't agree but function. I will look it up in one of my manuals and see if I can find a reference. Problem is they are for other models. Your DSC/ABS is working correctly? You are in Buffalo so you may have the same issue as my car had. The rear sensors were corroded into the rear hub. One worked but one did not. It is like they are being crushed by the housing.

Have a look at your rear sensors pull the screw and see if they wiggle if not they may have the same problem mine had. I replaced them and DSC started working.
 

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This happened to me today, around two weeks ago i got trifecta on dash and today code 2a appeared! So i guess it is the abs issue that triggered the code? Sailor is there a chance to know which is the bad abs sensor? I will inspect with bluebee method later and see...
 

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Update on Peake 18/ 2A "hardwire" code

Bringing this back up because I am getting the 2A code.

I recently replaced the RF wheel sensor and had the ABS module replaced under warranty by BBA. No other symptoms other than "tirecontrol inactive". which usually takes a few minutes to show.

So today I ran it down to my trusted indy and he ran some scans. It turns out that at around 20 mph, the scanner loses connection with the car OBD II port! His scanner shows wheel speeds on each wheel and I went for a ride. At 10 mph indicated, the numbers stop scrolling up, and a couple of seconds later, the scanner loses its connection. It is Bluetooth, but given the receiver is about 2 feet away for the plugged in module, it is pretty unlikely a ($15,000) scanner issue.

Now it could be an ABS module issue, but since it has recently been replaced by BBA under warranty and I am not seeing any other codes, I think that unlikely.

I am attaching a picture of the sine wave of each wheel (I believe the bottom axis is miliseconds, but I am not sure). The vertical axis is speed in mph.

I am also attaching a voltage graph. Seems that there is a downward spike each time the sine wave is measured. It pulls almost a whole volt, which to my electrically amateurish brain is way too much. So is the "hardwire "code have something to do with an electrical error, such as the alternator or voltage regulator malfunctioning? Again, NO OTHER CODES. It appears when the connection drops out, the code shows up. "Hardwire" sounds like either the ABS module or the RKW module behind the glove box is loosing communication.

One other thought from my indy. The RF wheel sensor replacement may have not been BMW OE, and it is possible a slight difference in spec is creating the different sine wave; enough to trip the code, but not enough to set off a check engine light.

He also thought that a non standard wheel bearing on that side could affect the reading, ( the 'reluctor"?) but no wheel bearing change recently. No apparent wheel bearing issues either.

So, the error code seems to be a loss of communication, or electrical issue causing the loss of communication (the voltage downward spike is 11.7, perhaps low enough for the momentary loss of communication?). Maybe with the additional information, we can finally figure this out. I am reluctant to start throwing parts at this, although I do have a spare RDW module courtesy of Clemster.

Regards,
Jerry

Oh, we disconnected each sensor and gave the inside connectors a quick clean and reconnected.
 

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How long have you had the inactive issue? As long as the code? I never fixed mine but at one point I switched modules from another car to test. When I put mine back in it stopped the code and sort of started working. Sort of only because I can't get the message that it is learning. It clearly is learning because if I don't do that, hold the button when I change tires I get the defect warning often. Also I get a defect warning when I have a leak. Sometimes I get a defect warning but there is nothing, only when ripping though. Clearly mine is at best partly working.

I would try unplugging the module and cleaning the contacts and plugging it back in. Possible that unplugging makes it do a full reboot so I might be worth starting the car with it out? Not sure, just guessing.
 

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How long have you had the inactive issue? As long as the code? I never fixed mine but at one point I switched modules from another car to test. When I put mine back in it stopped the code and sort of started working. Sort of only because I can't get the message that it is learning. It clearly is learning because if I don't do that, hold the button when I change tires I get the defect warning often. Also I get a defect warning when I have a leak. Sometimes I get a defect warning but there is nothing, only when ripping though. Clearly mine is at best partly working.

I would try unplugging the module and cleaning the contacts and plugging it back in. Possible that unplugging makes it do a full reboot so I might be worth starting the car with it out? Not sure, just guessing.
Thanks. No harm is trying to clean contacts on ABS module, but it was installed less than 2 months ago. I contacted BBA, they don't think it is their replacement module. They are looking to the wheel sensors (which I have had checked) and the transmission sensor (???). I think the electrical spike is interesting as below 11.7V I would think the computers start shutting down to protect themselves. So what would cause a big voltage drop at 10 mph?

In reading up on the RDW, I am wondering now if that is the culprit. Replaced once before, don't relish it a second time! :)

http://www.ge39.com/files/RDW.pdf

Regards,
Jerry
 

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No I am talking about the RDW. I think it might be different on 2000 cars. I have a module, my bad memory just tweeked that they intergarated in 9/2000. I will check WDS for you.
 

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I checked and there is no update or different diagrams by years. That said these are the most confusing diagrams I have looked at. They seem to also switch you to a RDC which is a real pressure system, but I don't think that was available. It does look like the sensors go to the ABS then the info gets sent to the tire module but it is hard to tell.

I knew that the module was behind the glove box but here is a pic, that is the most I got from my visit to the diagrams. Note this is the RDC which we don't have, but if memory serves me this is the same location I switched my module at. I will say it again MY2000 is my only experience.
Capture.JPG
 

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I know the module is there because I had it changed out once before. Late build MY '01.

Regards,
Jerry
 

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Been looking at the voltage drop, strange. If there was a short in the Module RDW then you could register a voltage drop elsewhere. from you PDF it says the voltage drop is at the brakeswitch which is term 15. If it is term 15 then your codes and symptoms could be a result of a failure somewhere else. Yerm 15 is used by many things.

If it was me I would pull the RDW and then test again. If things the same, look elsewhere... etc.
 

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Been looking at the voltage drop, strange. If there was a short in the Module RDW then you could register a voltage drop elsewhere. from you PDF it says the voltage drop is at the brakeswitch which is term 15. If it is term 15 then your codes and symptoms could be a result of a failure somewhere else. Yerm 15 is used by many things.

If it was me I would pull the RDW and then test again. If things the same, look elsewhere... etc.
I appreciate the follow up.

As an aside, after getting the car back, I cleared the last 2A code. Now have driven about 30 miles and no code. Very strange.

Will pursue this over the next week or two as I have time.

Again, much appreciated.

Regards,
Jerry
 
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