Canbus access from trunk module?

[evanevery]

I just pulled out the seats in my M4 in order to install a couple of custom Recaro Profi XL's along with a Rear Closeout, Roll Bar, etc. I noticed there is a computer module and a fuse box just behind the rear seat in the trunk. I didn't have a lot of time to record the ID on the module last night...

I was going to tap the CanBus lines off the FEM Body module behind the passenger kick panel and run the wires under the rear closeout and to my VBOX racing computer/video logger (which will be mounted on top of the closeout).

However, the module in the trunk behind the rear seat is obviously more convenient (if usable).

Anyone know what that module is? ...know if there is any CanBus wiring going to it? ...or perhaps even have a schematic to share?

Thanks in advance!

[aboulfad]

you obviously need ISTA/D for such a job and there are many modules in the rear... without a pic or more details, cant be of help. ISTA contains all schematics, location, pinout,... (aside from being The diagnostics software)

[evanevery]

Originally Posted by aboulfad

you obviously need ISTA/D for such a job and there are many modules in the rear... without a pic or more details, cant be of help. ISTA contains all schematics, location, pinout,... (aside from being The diagnostics software)

ISTA is for programming, right? I don't need that...

All I need to know is if there is a canbus feed to the module I'm referencing and what the wire colors or connector pinout would be...

The module I'm talking about is right behind the rear seat in the middle of the floor of the trunk, right next to the fuse panel...

If ISTA documents wiring colors, connectors, and locations - maybe some kind soul can look it up for me...

IOW - I already have an inductive tap which will grab the data - i just need to identify the associated wires.... (There should be two of them)

[heckyeahbro69]

Here is the module I believe you are referring to and the pin assignment.

[evanevery]

Yes that appears to be the module!

I don't see any wiring/connection info in your diagram though. Specifically I am looking for the PT-CAN CanBus wires. They are RED and RED/BLUE at the FEM module up front. Maybe/Probably the same colors in back (if they connect to that module at all). Not sure though...

[heckyeahbro69]

Originally Posted by evanevery

Yes that appears to be the module!

I don't see any wiring/connection info in your diagram though. Specifically I am looking for the PT-CAN CanBus wires. They are RED and RED/BLUE at the FEM module up front. Maybe/Probably the same colors in back (if they connect to that module at all). Not sure though...

I fixed the pics. There is connector and pin numbers. There is no pt can at the tcb according to this pin chart.


You can get it from the ekps though.

[evanevery]

Thanks!

I see some K-CAN wires in your pictures but many of the connector info is cut off at the bottom of your image... Do you see anything that says PT-CAN in the connector list?

[heckyeahbro69]

Originally Posted by evanevery

Thanks!

I see some K-CAN wires in your pictures but many of the connector info is cut off at the bottom of your image... Do you see anything that says PT-CAN in the connector list?

See new pics. No pt can at the tcb but I think the ekps might work for you given its location.

[evanevery]

Holy Crap! I owe you a beer! (or two)

Thanks for running that down. That seems very convenient!

[Habber]

Originally Posted by evanevery

Holy Crap! I owe you a beer! (or two)

Thanks for running that down. That seems very convenient!

He deserves an "appreciate".

[heckyeahbro69]

lol no problem. Keep me posted on how it turns out.

[aboulfad]

ISTA/D is for diagnostics... I even wrote that for you in my post! That nice soul used that tool to answer you above and you should get it as it would help you look for what you need and much more.

[Encanto]

I would not mess with the TCB.

The ASD module in turn has CAN wires that can be accessed easily and without any interference. And it is right there in the trunk.

[AllMyBMsAreDoubleYous]

I need a CAN tap that's unfiltered (since OBDII is filtered), and I'm thinking about using the connection to the light switch near the driver's window vent.

Are you using an IDC tap connector evanevery ?

[evanevery]

Originally Posted by Encanto

I would not mess with the TCB.

The ASD module in turn has CAN wires that can be accessed easily and without any interference. And it is right there in the trunk.

The identified module is the EKPS (Fuel Pump) and it really doesn't matter where you tap any one of the CanBus wires. They are just one big network. Same info everywhere. You're NOT messing with the associated module, just tapping the bus for info...

...and my video/data race logger (VBOX) uses an inductive tap so you don't actually have to cut, splice, or tap any wires. You just lay the two PT-CAN wires through the little inductive tap unit and it picks up the signal without interfering with it or touching it.

[Encanto]

If the TCB goes bad for whatever reason or it start having communications problems then the taps can invalidate the warranty. The ASD module on the other hand has the CAN wires available much easier at its connector and its function is not as critical/sensitive as the TCB.

Good luck in your project.

Originally Posted by evanevery

The identified module is the EKPS (Fuel Pump) and it really doesn't matter where you tap any one of the CanBus wires. They are just one big network. Same info everywhere. You're NOT messing with the associated module, just tapping the bus for info...

...and my video/data race logger (VBOX) uses an inductive tap so you don't actually have to cut, splice, or tap any wires. You just lay the two PT-CAN wires through the little inductive tap unit and it picks up the signal without interfering with it or touching it.

[evanevery]

We are talking about the EKPS module and NOT the TCB module... (Check the SECOND set of schematics)

I don't have any issue considering an alternative more convenient location but where do you see PT-CAN wires coming in/out of the ASD module?

It shouldn't really matter where you tap any of the CanBus network. If you trash the signal, it effects everything on the entire bus. Proximity of where you tap wrt to a specific module is not particularly relevant.

...and again, I'm not actually physically tapping anything. My device uses an inductive reader so it will not effect the signal or inductance of the circuit at all. The car will never know its there.

...and if I bust my Warranty I'll accept the consequences. I'm not one of those guys who tries to hide anything from my dealer.

So, if you know of PT-CAN wires going to the ASD, which connector and pins are they associated with?

(Also be aware that there is more than one CANBUS: K-CAN, KCAN-2, PT-CAN, PT-CAN2,... I need PT-CAN for "PowerTrain" data. K-CAN has completely different data....)

Thanks!

[Encanto]

Post# 4 shows the TCB -Telematics Communications Box.

Disregard: ASD module uses K-CAN.

Originally Posted by evanevery

I assume you are using the EKPS and TCB module identifiers interchangeably - cause the one behind the rear seat bolster is clearly named EKPS and controls the fuel pump...

I don't have any issue considering an alternative more convenient location but where do you see PT-CAN wires coming in/out of the ASD module? I assume thats the one I originally asked about which is next to the fuse panel...

It shouldn't really matter where you tap any of the CanBus network. If you trash the signal, it effects everything on the entire bus. Proximity of where you tap wrt to a specific module is not particularly relevant.

...and again, I'm not actually physically tapping anything. My device uses an inductive reader so it will not effect the signal or inductance of the circuit at all. The car will never know its there.

...and if I bust my Warranty I'll accept the consequences. I'm not one of those guys who tries to hide anything from my dealer.

So, if you know of PT-CAN wires going to the ASD, which connector and pins are they associated with?

(Also be aware that there is more than one CANBUS: K-CAN, KCAN-2, PT-CAN, PT-CAN2,... I need PT-CAN for "PowerTrain" data. K-CAN has completely different data....)

Thanks!

[evanevery]

Yes - but Post #6 is what we are talking about. Post #4 has been discounted/updated during the thread...

[evanevery]

Originally Posted by heckyeahbro69

lol no problem. Keep me posted on how it turns out.

Right where you said it was! Thanks for making things easy!

[aboulfad]

can you post pics of your inductive tap ? I haven't seen or heard about those since a very long time ... so curious of their design! TIA

[evanevery]

Inductive taps are not rocket science. They just detect the signal in wires without piercing the insulation. They basically work the same as ammeter clamps...

However, your solution must be capable of using an inductive clamp. (You just can't go to the hardware/electronics store and buy an "inductive clamp"). I'm pretty sure the clamp itself requires a bit of power to amplify the inductive signal it detects. Here is a link for the inductive clamp used by the VBOX:

http://www.racelogic.co.uk/usastore/...OX-Pro-and-HD2

Here are the photos I got from the VBOX vendor showing their clamp being attached to the PT-CAN wires located under the passenger kick panel. The process is obviously the same for attaching them near the fuel pump controller just under the Pass B pillar (I didn't think it necessary to take any of my own photos)...