1) The document describes a project to investigate issues with injectors falling out during the assembly process. A cable was designed and built to monitor the HUPE device that controls the injector needle movement. 2) By monitoring the HUPE signals for good and faulty parts, the team hopes to identify the root cause of the fallout issues. Having a monitoring process established provides a tool for troubleshooting future problems as well. 3) The project provided value by developing a new capability for understanding the proprietary HUPE device, potentially reducing waste from incorrectly replacing components without identification of the real issue.

1. Joshua Schall (TEF3.1.3/HDEV5) LG12 Project
Department | 4/21/2015 | © 2015 Robert Bosch LLC and affiliates. All rights reserved.
Gasoline Systems
HUPE Fallout Investigation
Department | 4/21/2015 | © 2015 Robert Bosch LLC and affiliates. All rights reserved.
Participants:
Joshua Schall TEF3.1.3
Joseph Williams MFE3.6.1
FLMs:
Jay Fegely MFO3.6.1
Jerry Hill TEF3.1.3
1

2. Department | 4/21/2015 | © 2015 Robert Bosch LLC and affiliates. All rights reserved.
Problem: HUPE Fallout
Gasoline Systems
2
HDEV5 high pressure
gasoline injectors have the
lift distance and closing time
of their needles set in three
process steps as they go
through Valve Group
Assembly Station 80.
As part of this process the
injector needles must be held
open or cycled open/closed
rapidly by energizing the coil
and creating a solenoid
action. The device which
controls the rapid cycling is
called a HUPE.

3. Department | 4/21/2015 | © 2015 Robert Bosch LLC and affiliates. All rights reserved.
Problem: HUPE Fallout
Gasoline Systems
3
The HUPE is a literal black box, which
controls the lift action of the injector needle
by sending trigger signals to the injector
coil, while also receiving voltage and
current feedback. For the intentions of this
project, injector fallout occurs during the
second step in the process at Valve Group
Assembly Station 80, Process Module B
(PMB), with the station displaying the
following fault messages regarding the
HUPE: “max voltage not reached” and
“max voltage control”. Parts are then
ejected from the production line and must
either be reworked or scrapped.
The specifics of the HUPE process are
proprietary to Bosch and are mostly
unknown at the user level in
manufacturing.

4. Department | 4/21/2015 | © 2015 Robert Bosch LLC and affiliates. All rights reserved.
4
Investigation: Researching the Root Cause
Gasoline Systems
Because of the proprietary nature
of the HUPE, troubleshooting these
faults can be very difficult. Without
understanding the entire process
and with few options, many times
the HUPE itself or the associated
contact blocks are blindly replaced.
With our efforts exhausted, the lead MFE for
this production area, Joe Williams, contacted
the lead plant in Bamberg (BaP). BaP TEF
suggested monitoring the HUPE and
provided basic plans for making the proper
connections.
Positive Contact BlockNegative Contact Block

5. Department | 4/21/2015 | © 2015 Robert Bosch LLC and affiliates. All rights reserved.
Action: Cable Construction
Gasoline Systems
5
I was tasked with creating a
monitoring cable based on the
information from BaP TEF as well as
coming up with a viable way to
interface with the HUPE that would
allow for data collection. An
oscilloscope would allow us to view
the four monitoring channels of the
HUPE as waveforms and give us the
option of recording this data so I
based the cable design around this
concept. Two of the HUPE channels
are low trigger signal voltages, one is
a higher voltage across the coil and
one is the amperage through the coil.
HUPE PMC HUPE PMB

6. Department | 4/21/2015 | © 2015 Robert Bosch LLC and affiliates. All rights reserved.
Action: Cable Construction
Gasoline Systems
6
Using electrical theory, I calculated the
maximum voltages and current loads
we could expect to encounter based on
the information from BaP TEF. It was
necessary to put a 100Ω resistor in
series for two of the channels so power
dissipation for these also had to be
calculated. Using American Wire
Gauge (AWG) standards, each
conductor had to be no smaller than
31AWG and the resistors had to be
capable of dissipating 1 watt. It would
also be beneficial to use twisted pairs
for each channel as this method greatly
cuts down on interference from
electrical noise.

7. Department | 4/21/2015 | © 2015 Robert Bosch LLC and affiliates. All rights reserved.
Action: Cable Construction
Gasoline Systems
7
Standard Category 5 network cable
already contains four color coded
twisted pairs of 23AWG solid
conductors so it was perfect for my
needs. With research and some
experimentation with various
construction methods I came up with a
plan and a parts list that would suit my
needs and arranged for purchase
through the MOE3.6 maintenance
planner.

8. Department | 4/21/2015 | © 2015 Robert Bosch LLC and affiliates. All rights reserved.
Action: Cable Construction
Gasoline Systems
8
Referencing the pin-out diagram provided by BaP
TEF I made the necessary solder connections on
a Lemo CLAD99 16 pin connector. This is the
direct interface with the HUPE.

9. Department | 4/21/2015 | © 2015 Robert Bosch LLC and affiliates. All rights reserved.
Action: Cable Construction
Gasoline Systems
9
BNC connectors are necessary for
interfacing with the oscilloscope, one
for each channel. I chose solder over
crimp connectors for the strength of
the joint and to ensure a better quality
monitoring signal. Using solder
connections also made it easier to
install the series resistors on the
voltage and current monitoring
channels.

10. Department | 4/21/2015 | © 2015 Robert Bosch LLC and affiliates. All rights reserved.
Monitoring: Testing and Data Collection
Gasoline Systems
10
After successfully testing
each of the cables, we
were able to actually
begin monitoring
production parts.
Waveforms of good parts
were compared to those
of the fallout parts when
they were re-run through
the station. Unfortunately,
the data recording
software accompanying
the oscilloscope was fairly
dated and didn’t function
as well as hoped. Video
had to be taken of the
waveforms as each part
passed through the line.

11. Department | 4/21/2015 | © 2015 Robert Bosch LLC and affiliates. All rights reserved.
Conclusion: Results and Returns
Gasoline Systems
11
I consider this project to be a multi faceted success. This was a fun project to plan and carry out. The
cable construction process involved some trial and error but overall went very smoothly, with the only
major issues being getting parts delivered in a timely manner. Diagrams and notes on the process
have been saved and will be put in a central location on the server to allow for others to easily build
more cables in the future as our production lines multiply.
The returns on this project are two fold. Obviously quality is affected as this was the driving force
behind the project to begin with. Although investigation and monitoring in this case are ongoing,
having a way to monitor the HUPE has provided an option that previously did not exist. In the past it
was accepted that HUPE fallout was scrap when it continued to fail after attempted rework. Now, with
continued research, a root cause can hopefully be found and preventative measures can be
implemented to eliminate it. This is true not only in this particular case but also with any other
instances which may happen in the future. Now that there is a monitoring process, there will always be
a monitoring process.

12. 12 Department | 4/21/2015 | © 2015 Robert Bosch LLC and affiliates. All rights reserved.
Conclusion: Results and Returns
Gasoline Systems
From a maintenance standpoint, it is always frustrating to encounter a component you know little to
nothing about. And even more frustrating to find there is almost zero documentation on it. Because of
the proprietary nature of the HUPE we may never know everything about how it really works. But
having an option to monitor trigger and feedback signals partially fills a hole that used to exist in the
troubleshooting process. In the past when there were issues with a related process, the HUPE was
always in question to some degree; to the point of forcing us to sometimes blindly replace components
such as the contact blocks and the HUPE itself. This is not an ideal situation. In the future there will
be a way to rule out or confirm the HUPE as malfunctioning without spending the time and money
replacing it.
Because it is new and uncharted territory, the future of HUPE monitoring will be a learning process.
But knowledge gained from this experience, and further related experiences, will only further our
understanding of a component which has historically been largely a mystery.