EPB Retrofit ... the way to Stop & Go

My seller has left me with no other option but to go public.

My test.

And this is test performed by @dnoermann :thumbsup:.
As @pulken has suggested my controller has a hole under the sticker and eeprom chip has been resoldered.

Additionally the print on the sticker is very low quality & VW logo is missing.
Poor attempt to make it look genuine and I got fooled anyways.

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Be careful with this module I bought one from that specific seller it was not working. Same did a another guy in Turkey same module, does not work. I bet you will have a hole under your label at the TRW location where they have drilled in and modified the EEPROM.
So i got the Unit from @Robert for analysis.
It had the same hole, the SPI eeprom was changed.
But on Robert's unit they made the soldering bad, so a short between Pins 5 (Data) and 6 (Clock) was making problems.
I repaired this, but still unit is Dead.
I measured 5V from Pin 8 (VCC) to 4 (VSS) so part is placed correctly. And unit is working a bit, at least 5V Power works :)
I guess this is a Audi EPB that was converted to 56D by changing SPI eeprom contend, and on @Robert Unit they forgot to programm Eeprom.

Attached the Picture to see short.
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I could not read Eeprom when installed.
I will desolder it and read it externally to validate.
 
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My play with EPB switches has come to the successful end :).

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Unfortunately, as posted here, switch 5N0927225B is not direct replacement for 56D927225.

Unit 5N0927225B uses 6 pins for actual EPB switch with 2 internal capacitors and unit 56D927225 uses 4 pins with 4 internal diodes.
Additionally micro switches are also different, first one has 2 x (separate N/O contacts & separate N/C contacts) against second one with 2 x ( double N/O, C, N/C).

Taking into account the size of internal PCB and SMD components I decided to transfer 2 micro switches from 56D927225 to 5N0927225B.
Illumination and all indicators are used directly from 5N0 PCB with 56D micro switches wired externally to the 56D PCB.

What's worth to mention is that unit 5N0927225B is identical physically and electronically to 5N0927225A.

Alternative method and probably much more straightforward would be to use 7N0927225B unit.
It uses 16 pin plug (part number 1K0927928).
Pins 1, 2, 3 & 4 correspond directly to the wiring of 56D927225 unit.
Pin 5(+) & 6(-) are for illumination.
Pin 9(+) & 10(-) are for EPB ON indicator.
Pin 12(-) & 13(+ in) are for Auto Hold indicator.
Pin 13(+ in) & 14(+ out) are for Auto Hold switch.
Remaining 5 pins are not in use.
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Summarising all 3 (16 pin) units mentioned above 5N0927225A, 5N0927225B & 7N0927225B look identical externally
but only 7N0927225B has the same electronic internals as 56D927225 :thumbsup:.

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And finally my first lot of EPB controllers has arrived.
This time brand new and genuine VW made by TRW.
Fully functioning and working.
Already tested on bench and in the vehicle :thumbsup:.
Also with @dnoermann's involvement
we have verified BCM compatibility and these modules work with all revisions of
BCM PQ25 Max4 7E0 937 090(no letter/B/C/D):grin bounce:.

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Ladies and gentlemen, let me present you my (world's first :grin bounce:)
VW Transporter/Multivan/Caravelle T6 with Electronic Parking Brake :D


I just need to complete the wiring of my PARKING BRAKE indicator on my INSTRUMENT CLUSTER and the AUTO HOLD.
 
Ladies and gentlemen, let me present you my (world's first?)
VW Transporter/Multivan/Caravelle T6 with Electronic Parking Brake :D


I just need to complete the wiring of my PARKING BRAKE indicator in INSTRUMENT CLUSTER and AUTO HOLD.
Hi, cool project.

Is it possible to run the brakes with this EPB controller alone? Or does it need to be connected to ECU?
 
ECU? Do you mean CAN bus?
Yes, I meant if it needs to be actively getting valid data from the can bus to lock/release the brakes, or would it run standalone. I assume it waits or requests some data like vehicle speed or other, but would it run without it?
Sorry if this is a stupid question, I don't really have much experience with this.
 
First release of EPB was implemented by BMW on 7 Series (E65) back in 2001.

Electronic Parking Brake as a system has been designed to be integrated component of vehicle network system.
It exchanges a lot of info/data, via CAN-Bus, with Engine, DSG, ACC, IC, BCM, etc.
Additionally EPB is a certified replacement of Manual Parking Brake
and thus compliant with the following standards FMVSS 105, FMVSS 135, ECE 13H.
And this means that EPB can also be used as a secondary/emergency brake :grin bounce:.

At glance EPB appears to be just 2 servomotor calipers controlled by the switch
but this is only one part of this very sophisticated system :cool:.
Generally servomotors are being used at speed of 7 km/h and lower
which means that they are designed for stationary use as a purely parking brake.

Applying EPB at higher speeds is the second part of this system.
In such a scenario EPB controller sends CAN frames to the ABS and requests hydraulic braking to take place.
This braking is called "Emergency Braking" and it is capable of safely stopping vehicle in a very controlled manner from any speed.
It uses anti-lock functionality and by default it brakes using all 4 wheels with predefined intensity.
EPB adaptations allow for a lot of adjustments and tweaks,
among which "Emergency Braking" intensity and braking axle selection are the most important.
There is a selection of 7 intensity levels and "Emergency Braking" can be set to use rear axle only or both.

So taking into account all of the above and what is most important safety of all road users EPB can not be used as a stand alone system.
The most obvious concern would be applying EPB via servomotors and locking rear axle wheels at high speed :eek:.
 
First release of EPB was implemented by BMW on 7 Series (E65) back in 2001.

Electronic Parking Brake as a system has been designed to be integrated component of vehicle network system.
It exchanges a lot of info/data, via Power-train CAN-Bus, with Engine, DSG, ACC, IC, BCM, etc.
Additionally EPB is a certified replacement of Manual Parking Brake
and thus compliant with the following standards FMVSS 105, FMVSS 135, ECE 13H.
And this means that EPB can also be used as a secondary/emergency brake :grin bounce:.

At glance EPB appears to be just 2 servomotor calipers controlled by the switch
but this is only one part of this very sophisticated system :cool:.
Generally servomotors are being used at speed of 8km/h and lower
which means that they are designed for stationary use as a purely parking brake.

Applying EPB at higher speeds is the second part of this system.
In such a scenario EPB controller sends CAN messages to the ABS and requests hydraulic braking to take place.
This braking is called "Emergency Braking" and it is capable of safely stopping vehicle in very controlled manner from any speed.
It uses anti-lock functionality and by default it brakes using all 4 wheels with predefined intensity.
EPB adaptations allow for a lot of adjustments and tweaks,
among which "Emergency Braking" intensity and braking axle selection are the most important.
There is a selection of 7 intensity levels and "Emergency Braking" can be set to use rear axle only or both.

So taking into account all of the above and what is most important safety of all road users EPB can not be used as a stand alone system.
The most obvious concern would be applying EPB via servomotors and locking rear axle wheels at high speed :eek:.

Thanks a lot for your comprehensive answer.
So what would happen when there is a break in the connection from EPB controller to the CAN (let's say corroded wires).
I see that some systems use additional signal from DSC which is a single line speed signal. But what in case both CAN and this single line signal are cut?

Would that mean that the user cannot apply the parking brake?
 
Hej Kuba ;).

If CAN-bus is disconnected from EPB controller you can still apply parking brake via servomotors but EPB switch has to be kept in up position.
Once released servomotors open calipers automatically.

And just to be clear we don't need to reinvent the wheel.
This is well designed and certified technology that is used across whole automotive industry.
It comes by default with majority of new vehicles nowadays.
 
FOR SALE !
Manual Parking Brake system.

Open to offers, perfect condition.
Full kit includes:
2 off caliper
3 off cable
1 off lever
2 off cover
1 off sensor switch

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Only serious offers will be considered.
No time wasters :laugh:.
 
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