Download SMT7 step by step installation guide

SMT7 step by step installation guide.
Piggyback installation can get a little tricky for the first time user. The purpose of this
document is to show you how to break down an installation into separate components,
simplifying the installation and helping isolate faults.
Please note that this manual does not replace the developer’s manual and mainly deals
with a standard tuning application, not peripherals like boost control and closed loop
tuning.
We will go through this by generating an SMT7 diagram, users of the SMT6 may note
that the layout of the diagram is a little different, you shouldn’t be overly concerned
the concepts are the same.
The following shows a completed SMT7 wiring diagram.
The diagram consists of three different tiers.
The top tier contains all the vehicles information, name make etc.
The middle tier shows all the ecu information and contains a picture of the ecu’s
connector plug. This is good starting point when checking to see if you have the
correct diagram, if your plug does not look the same, you have the wrong diagram.
The bottom tier has all the wiring information; here is the main difference to the older
SMT6 diagrams. Typically you have two different types of connections, the T and the
cut connection, see Appendix 1 for a description of what they are.
The diagram above shows a T connection; in this diagram shows the power wire
going to pin 37 of the ecu is connected to the red pin 10 of the 18-way connector on
the SMT7.
The second is a cut connection; once again see Appendix 1 for a description.
The above shows an intercepted MAP sensor connection going to pin 7 of the ecu, the
wire from the engine bay is cut and connected to pin 8-18 of the SMT7, the ecu side
of the cut is then connected to pin 1-16 of the SMT7.
It is highly recommended that you use a scope to find signal traces, multimeters can
work but they don’t show noise, often are not fast enough to detect switching and are
completely useless when it comes to identifying crank trigger patterns.
Step 1:
Power and ground.
Never underestimate these two connections; they are connected to all the other steps
from here out, if for some reason power falls away, everything else shuts down. If
there is noise on the line all other SMT7 components will have this noise.
Power and ground connections are T’d connections see appendix 1 at the end of this
note for a description of T’d connections.
For power you are looking for a 12V signal, first prize is to find the ECU’s ignition
switch power or main engine management power, if you have a pin-out description of
the ecu it will be labeled as such on the diagram. If you don’t have a diagram follow
these steps:
a)
b)
c)
d)
e)
f)
g)
h)
Use the oscilloscope to find a 12V signal.
Turn ignition off, make sure the 12V goes away, this isn’t absolutely
critical the SMT7 only draws about 100mA of current so it wont draw to
much from your battery, but if given the option I would like to have the
unit switched off if I can.
Turn ignition back on without cranking; make sure its goes to 12V.
Crank the engine; you should see the voltage drop a little as the starter
motor draws power away from the battery, this is fine just as long as the
voltage does not drop below 6V, the SMT7 would reset if this happened.
Once the car is running it will sit as 12V again.
Blip the throttle and make sure the level stays stable.
Two things to look out for are excessive noise and pulsing, it’s a common
mistake to connect power to one of the injector signals they tend to look
like nice power lines until you start the car.
Also watch out for things like clutch switches, aircon supply lines and
drive transmission switches they can also look like supply points but
switch under certain conditions.
Some ecu’s, Toyota’s in particular, have current limits on there 12V lines,
you may find a 12Vsignal falls away when the SMT7 is connected to it.
You will need to find another 12V pin.
If ever in doubt and you feel a fault is power related connect the SMT7 directly to that
battery, if the problem goes away then you where correct, find another power pickup
point. Alternatively you can keep the SMT7 connected to the battery, I would
recommend putting a 200mA in line for safety reasons.
For ground connections do the following:
a)
b)
c)
d)
e)
f)
g)
Use the oscilloscope to find a 0V signal.
Turn ignition off; make sure it stays at 0V.
Turn ignition back on without cranking; make sure it remains at 0V.
Crank the engine, the signal should stay 0V.
Blip the throttle and make sure the level stays stable.
Two things to look out for are excessive noise and pulsing.
Also what out for things like clutch switches, aircon supply lines and drive
transmission switches they can also look like ground points but switch under
certain conditions.
Be aware of any offset voltages for example a voltage level of 500mV instead of 0.
An offset voltage will result in an offset on the SMT7’s trigger level and could result
in bad signal detection during cranking when the signal is weak.
Your wire diagram should now look like this.
Now you are ready to test communications on the unit, connect the SMT7 to the
laptop as shown in the following diagram
Laptop
Comm’s
port
Comm’s cable
Comm’s cable
SMT7
UNI5
Unit
Harness
connector
Power (red)
Wiring harness
Ground (black)
WARNING:
If the laptop or computer is connected to a mains wall socket or on charge for the
above communications, it is possible that the computer port will “BLOW” the
communication port on the SMT7. To be safe, connect the comms cable first,
switch the PC ON and then turn ON the car’s ignition. Avoid disconnecting and
reconnecting comms cable while Ignition is ON as this could damage the SMT7.
Run the SMT7 tuning software and ensure that when the unit is powered up you get
communications with it, you can confirm this by looking at the bottom left hand side
of the tuning screen, you should see a little green block flashing on and off.
If the SMT7 is not communicating with the PC, check these common problems:
CAUTION:
ALWAYS turn the ignition OFF before removing and inserting the comm’s
cable. Leaving the ignition ON, could damage the PC and or the SMT7.
1)
Re-check the power connection. Make sure there is no noise and that it is a
stable voltage i.e. non-switching.
2)
Make sure that the power stays ON constantly. You may be connected to
an alternate supply that only stays on for a few minutes and then switches off.
3)
Check the comms cable for continuity. The cable could be damaged or
disconnected during the installation
4)
Make sure the laptop’s comms port is working. Try another laptop or PC
that you know has an operational comms port.
5)
Connect to the correct comms port. In the Windows tuning software, check
to see if the correct comms port is being used. This can be found on the main
parent screen.
6)
Contact Perfect Power Technical Support if the above checks have not
solved the problem. When contacting Perfect Power at info@perfectpower,com,
please provide as much information on the installation as possible.
You should only continue with the rest of the installation, if there is communication
with the SMT7. Communication is essential for the rest of the installation and tuning.
Step2:
Deflection
Deflection is a simple T’d connection (see appendix 1 for description). To identify the
signal do the following:
a)
b)
c)
d)
e)
Start the engine
Look for a signal with a slight offset.
Blip the throttle, the signal should blip along with it.
Switch ignition off then turn it back on without starting the engine.
Blip the throttle and the signal should shift once again. MAP/MAS/AFM
signals can look a lot like TPS signals, if the engine is not running there is no
airflow, if the signal still fluctuates it has to be the TPS signal.
Add the following to your diagram.
Go to the analog 1 screen.
Make sure that the unit is online then follow these steps:
1) Take your foot off the throttle; make a note of the deflection voltage on the
left hand side of the screen.
2) With just ignition on and without the engine running put your foot flat and
make a note of the deflection voltage.
3) Click the set scales button, then select the deflection tab off the next menu.
4) Make the low calibration value 5% more than the recorded reading in step 1.
5) Make the high calibration value 5% less than the recorded reading in step 2.
6) Click on Apply linear or Apply non-linear depending on what curve you want,
click on close.
7) You should be taken back to the analog 1 screen, blip the throttle and make
sure the green cursor moves laterally across the screen.
8) Click on Make permanent to make these changes permanent.
Step 3:
Fuel
The most common signal used for of fuel manipulation is the MAP/MAS/Airflow
sensor, for simplicity I will call it the load sensor from here on.
The load sensors signal should be somewhere between 0-5Vdc, please note that the
SMT7 cannot read frequency based sensors, only analog, frequency based sensors are
still supported by the SMT6.
Signal tracing is more or less the same as the deflection’s signal:
1) Look for a signal with a slight dc offset.
2) Blip the throttle and the signal should change.
3) Switch the engine off and turn ignition on without starting the engine. The
measured signal should not fluctuate at all when blipping the throttle while the
engine is not running, how can it there is no airflow.
This would be the first cut signal of the installation, refer to appendix 1 for a brief
description of this.
1)
2)
3)
4)
Cut the wire going to the ecu.
The engine side of the cut gets connected to pin 8-18 of the SMT7.
Pin 1-16 of the ecu gets connected the ecu side of the cut.
Go to the analog1 map.
5) Make sure Analog1 zero offset is set to 0 and the limits are 0-5V.
6) Start the car, make sure it idles correctly, you can then test to see if the settings
work by putting small values in the Analog1 zero offset box (0.05 to 0.1). You
should hear a difference in the running of the engine when playing with this
value.
7) Get the engine to stall by putting a big value in this box (2V should do it).
8) Set Analog1 zero offset back to zero when you are finished.
You diagram should now look like this:
Step 4:
Ignition modifications
If you are new to piggyback installations I would suggest reading Appendix 2 for a
brief description of the different types of signals before continuing.
Users of the SMT6 should be aware that the crank detection circuitry is very different
in the SMT7 and should pay careful attention from here on.
The first thing you need to do is identify which trigger pattern the car has and select it
from the trigger list by clicking on the trigger type button found on the parent screen.
The following menu will come on screen.
Click on the appropriate signal and then click on the Load Selected button, don’t
forget to make permanent after this. The trigger pattern will be activated when the
unit is reset so go to the ignition map, click on a map cell and type xx to reset the unit.
The selected trigger pattern should be displayed in the global settings box of the
ignition map.
Global settings are very simple in the SMT7, most of the information is held in the
trigger pattern. The only setting you will have to set is the high trigger level setting on
the ignition map if applicable. The other settings are limits and launch control, they
are not important at this stage except that launch control must be disabled.
The SMT7 uses a differential amplifier to detect a signal, I wont go into to much
detail here, all you really need to know if is that it generates a signal based on the
difference between its two inputs, which is why there are two CB1 and CB2 inputs.
There are three common types of wiring configurations in piggybacking, balanced
magnetic, non-balanced magnetic and digital/hall. Here is how you wire each setup.
Balanced magnetic:
Most commonly found in cars that have missing tooth signals, this type of setup takes
a reading from both polls of the magnetic sensor and therefore two signals are found
on the harness of the ecu.
When manually tracing signals with a scope, if you find a missing tooth signal don’t
stop your search until you have checked all other pins on the ecu and ensured there
isn’t another signal.
The balanced signal is the most straight forward of the three signal types:
1) Examine one of the balanced signals and determine whether it has a positive
or negative trigger.
2) If it is positive then wire its sensor side to 2-18 and its ecu side to 5-18.
3) If it is negative then wire its sensor side to 3-18 and its ecu side to 4-18.
4) The other balanced wire would be connected in whatever configuration was
not used in steps 2 and 3.
5) Ensure that the high level trigger global setting on the ignition screen is
disabled.
ECU
Sensor
Positive signal
Cb1+
Negative signal
Cb1-
SMT7
Ignition #1 + out
Ignition #1 - out
Non-balanced magnetic.
This type of signal could range from missing tooth signals, standard signals to odd
signals, the point is there is only one signal and it is a bipolar signal (swings on either
side of the ground point).
Connection is as follows:
1) Determine if it is a positive or negative going signal (see appendix 2). Then
cut the wire.
2) If it is a positive going signal connect the sensor side to CB1+ (2-18), if it is
negative connect it to CB1- (3-18).
3) Whichever pin was not used in step 2 gets connected to ground.
4) The ecu side of the cut gets connected to Ignition #1 bipolar out (5-16).
5) Make sure the global setting High level trigger is set off.
ECU
Sensor
Positive signal
Cb1+
Cb1Ground
SMT7
Ignition #1 Bipolar out
Hall effect.
The concept here is similar to the non-balanced signal in that it is just a single signal
but it is different in that the signal is digital and does not swing on either side of the
ground line.
These signals can also be missing tooth, standard signals or odd signals.
Wiring is as follows:
1) Once you have identified the signal wire determine if it is positive or negative
trigger. Then cut the wire.
2) If it is a positive signal connect the sensor side to CB1+ (2-18), if it is negative
connect it to CB1- (3-18).
3) The unused input in step 2 gets connected to ground.
4) Connect a pull-up wire (10-16) to the sensor side of the cut as well.
5) If it is a positive signal connect the ecu side of the cut to Ignition #1 + out (518) or if it is negative connect Ignition #1 – (4-18) out to the ecu side of the
cut.
6) Enable the high level trigger setting in global settings.
7) If the car does not start try using pin 5-16 instead of the pin selected in step 5.
ECU
Sensor
Positive signal
Cb1+
SMT7
Ignition #1 + out
Cb1Ground
Pull-up
You should be able to start the car now, go to the ignition map and make sure that the
rpm reading is more or less the same as on the dash board.
If the car will not start check the following:
1) Ensure that the signal with correct polarity is wired to the appropriate CB1
positive or negative input.
2) Double check to make sure that you don’t have a balanced signal on the ecu.
3) Make sure you have the correct trigger pattern loaded in the unit by switching
the unit and software off. Re-start both software and unit. Then make sure the
correct trigger pattern is displayed in the ignition maps global settings.
4) The un-used CB1 input must be grounded in Hall and non-balanced wiring
configurations.
Once the engine is up and running go to the ignition map and make a note of its rpm
at idle. At the same time make a note of the maximum rpm you would like to tune at.
After this select the click on the set scales button. Click on the RPM tab on the next
screen.
Set the Low calibration point so that the car idles on the second row of the ignition
map, all modifications are ignored on the bottom row to allow for easy starting, the
car could develop idle problems if allow to oscillate between the first and second row.
Set the High calibration point to the highest rpm you want to tune at, note that if the
cars rpm goes beyond this point the last map value will apply from there onwards.
Click the Apply linear or Apply non-linear button to enable these settings. Then click
on Make Permanent to make the changes permanent.
Check to see the timing works by putting values in the cells, advancing the timing
should raise rpm, retarding should drop rpm.
The following picture shows a complete wiring diagram for a balanced setup.
Conclusion:
Experience with the SMT6 has shown that using the installation guide step by step
process significantly reduced the number of technical queries and is a proven method
of installation when a confirmed wiring diagram cannot be found.
I am more than happy to expand on the text if you feel its necessary, if you have any
suggestions or queries you can get a hold of us at our help desk at
[email protected].
Happy tuning.
Appendix 1
T’d connection:
This type of connection is used when no signal modifications take place; the SMT7
wire is tapping a signal or supply from a wire on the ECU.
Insulation tape
To SMT7 unit
To ECU
Insulation
Solder joint
From engine
Cut connection:
Used when signal modification takes place, common to analog1, analog2 and ignition
modification wires.
Insulation tape
Insulation tape
To ECU
To SMT7
Insulation
Solder joints
From engine
Appendix 2: (Basic signal 101)
There are two common types of sensor signals,
the hall-effect signal and the magnetic.
Magnetic signals:
Magnetic signals are generated when the tooth of a pickup wheel interrupts the
magnetic field of the sensor, which in turn creates a signal along the wire. This signal
is normally a sine wave and would be displayed as shown in the diagram below on a
scope.
Voltage
0V
Time
Because the signal relies on the amount of energy present when the pin crosses the
sensor the signal is pretty weak approx 2Vp-p (peak to peak) during idle and then
strong at higher rpm (I have seen 20Vp-p).
Digital signals:
Digital means you are going to have some sort of on off condition and as a result the
sensors output is some sort of transistor based switch. The two most common types of
sensors are optically or magnetically activated, an optical type has some sort of wheel
with windows in it that cuts a light source to the sensor, this activates a switch and
generates a signal. The magnetic hall works on the same principle as the magnetic
sensor except it has a switching circuit added, the magnetic field switches this circuit
on and off to get a digital type response.
A scope trace for this signal would look like the diagram below, this signal is
commonly either 0-5V or 0-12V.
Voltage
0V
Time
STANDARD SIGNAL
The standard signal generates a pulse for every cylinder pair, in other words if it was a
4 cylinder engine you would have 2 pulses for every single crank revolution. When
this manual was written the SMT7 had trigger patterns for 4,6 and 8 cylinder engines.
Cars that generate multiple tooth standard signals can be modified with the SMT6 if
the SMT7 does not have its trigger type loaded in it.
MISSING TOOTH SIGNAL
For missing tooth signals, the pickup reads a wheel with a number of teeth on it similar to a gear found on a bicycle. The most common numbers of teeth on the
“gear” tends to be either 60 (which is normally found on Bosch systems) or 36
(commonly used in Fords and Toyota’s). Bosch systems normally run 60-2 wheels,
Fords 36-1 and most late model Toyota’s have 36-2 wheels.
What makes the missing tooth signal, is that either one or two teeth are taken off the
gear resulting in a gap in the signal where the teeth are missing. The missing tooth
normally depicts one complete crank revolution. There are also two types of pickups
or sensors used with missing tooth signals, either a hall sensor or a magnetic sensor.
The hall sensor signal, is easy to see since it is just missing one or two of its square
waves (see below). The magnetic sensor signal, results in a bit of a strange crossing
when encountering the missing tooth (see below).
Voltage
Voltage
0V
0V
Time
Time
When defining the type of missing tooth wheel you have, you need to include the
missing teeth. An example would be to physically count 58 teeth on the wheel and
physically count two missing teeth. Adding all the teeth together, this would be a 60
tooth wheel. In this example, the missing tooth wheel is referred to as a 60 minus 2 or
60 – 2.
If the SMT7 does not have the pattern loaded for your particular missing tooth setup
the SMT6 will be able to modify your signal.
ODD SIGNALS
Voltage
0V
Time
When advancing the ignition signal in our older SMT6 unit, the SMT6 needed to
predict a future signal revolution so as to generate what the signal should look like.
This means that the SMT6 had to be programmed to know what the signal looks like.
Since the previous ignition type signals are uniform in pattern, the SMT6 can easily
advance these signals. With the “ODD” ignition signal, the pattern is non-uniform
and therefore it was not possible to advance. Retarding is simple since the unit just
has to record what is happening and delay.
Odd signals are normally found in Nissans, many American cars like the Chevrolets,
Subaru’s and cars with the LS1 engine.
The SMT7 is different it has a pattern loaded into its memory, it knows what the
signal is supposed to look like and is therefore able to predict a signal and advance it.
If it does not have the pattern get in contact with us at [email protected] for
details on how to get a pattern made.
Otherwise you also have the option of using the SMT6 to retard the signal.
Trigger polarity and level.
It is important that the basic waveforms have been understood from the previous
sections above.
The shape of a waveform is usually not critical, but what is important is the trigger
level of the SMT7 and where the signal voltage crosses this level.
Think of the trigger level of the SMT7 as a single line. On the above ignition signal
types this could be the 0V line, referred to as the trigger voltage. The SMT7 reads
or triggers when a signal rises above or drops below the trigger voltage. A signal
that moves from below trigger voltage to above trigger voltage, is the positive
edge trigger. From above the trigger voltage to below, is the negative edge
trigger.
The SMT7 does not set its polarity in its global setting like the SMT6 did, this is
done in its wiring, signals with a positive trigger should be wired to the CB1+ pin
(2-18) and signals with a negative trigger are connected to the CB1- pin (3-18).
HALL EFFECT SIGNAL
Take a look at the signal on a scope, the edge that wiggles the least will give you
your most stable reference and should be selected as your trigger edge. The
signal below would be an example of a positive trigger signal.
Wiggle
Voltage
0V
Time
The dots represent a trigger point detected by the SMT7 and the level is marked
by the dotted line
Because a hall sensor does not cross the zero voltage point low level triggering
would make it very susceptible to noise and there is a risk it may not trigger at all
if for some reason the trigger level does not go completely to ground. It is best to
switch to high level triggering on these signals.
MAGNETIC WAVE SIGNAL
This diagram shows a typical magnetic wave. The dots represent a trigger point
detected by the SMT7 and the level is marked by the dotted line. The signal can either
trigger on a low to high rising edge or a high to low falling edge. The grey is rising,
while the white is falling.
Due to the curvature of the signal at high voltages and the fact that the signal is pretty
weak during cranking magnetic signals are normally set to low level triggering.
Voltage
Like triggers Like triggers
Top
Top
Top
Top
Top
Top
0V
Bottom
Bottom
Like triggers Like triggers
Bottom
Bottom
Bottom
Bottom
Time
To determine the polarity of a missing tooth signal take a look at the missing tooth
squiggle, if it moves from a positive voltage to a negative it is has a negative trigger,
conversely if it moves from a negative voltage to a positive then it has a positive
trigger. The following example is a negative trigger signal.
Voltage
0V
Time
Although I doubt it’s a technically accepted term squiggle identification works very
well with all signal types, when working with other magnetic trigger types (for
example Subaru) look for the squiggle to determine polarity.
You should now have a decent foundation on signal identification, the rest will
become clearer with experience.