How to use the MegaSquirt 5.0 Mustang Adapter Harness

Using the Megasquirt-II and EEC-IV Harness with TFI

MegaSquirt-II PCBv3.0 Mods Required: 

• Input mod:  You install a 2k 1/4w resistor in place of D2.  Jumper D1. Jumper TachSelect to OptoIn, XG1 to XG2, and TSEL to OptoOut.
• Output mod: Run a jumper wire from JS10 to IGBTIN and jumper IGBTOUT to IGN.
• Fast idle mods:
  • Remove Q20 and D8.
  • Remove R39 and install a jumper in its place.
  • Install a TIP120/121/122 in place of Q4. For more information, see our MK-PWMIAC page.

  For fan control on a '94-'95, you can add a pair of relay control mod kits in the proto area, or swap the IAC output wires so you have JS1 wired to IAC1A and JS3 wired to IAC2A. (JS0 and JS2 can be left disconnected).

MegaSquirt-II PCBv3.57 Mods Required: 

• Input mod:  You install a 2k 1/4w resistor between pins 2 and 3 of the JP1 main board jumper. Put jumper J1 in the 1-2 position, and connect the XG1-XG2 jumper.
• Output mod: Run a jumper wire from JS10 to IGBTIN and install a BIP373 or TIP120 in the Q16 slot.
• No fast idle mod is needed.
• For fan control on a '94-'95, you can add a pair of relay control mod kits, or swap the IAC output wires so you have JS1 wired to IAC1A and JS3 wired to IAC2A. (JS0 and JS2 can be left disconnected).

Megatune Ignition Configuration:

(from B&G's TFI Control page for the MS-II)

• Trigger offset = 10 degrees (this will vary, depending on the distributor orientation, see below)
• Ignition Input Capture to 'Falling Edge'
• Cranking Trigger to 'Trigger Rise'
• Coil Charging Scheme to 'Standard Coil Charging'
• Spark Output to 'Going High (Inverted)'

Then set the dwell setting to 8.0 milliseconds with no battery voltage compensation. This will get the spark output to closely imitate the square wave signal that the EEC-IV computer sends out.

If you are using MS2/Extra, you will use Basic Trigger mode, and a fixed duty dwell with a 50% duty cycle.

More information on setting Trigger Offset:

You must also set the initial position of the trigger (called the 'trigger offset'), then check it using the Trigger Wizard in MegaTune  (Tools Menu).  The trigger offset setting will vary according to your distributor position (where it is in rotation) but you'll need to set it properly...  Basically you use the Trigger Wizard and adjust the 'trigger offset' and/or twist your distributor until the advance number in the Trigger Wizard matches what you're reading with your timing light.  The +/- buttons on the trigger wizard will adjust your trigger offset.  You'll need to use these buttons and a timing light to make the number on your light, and the big number on the left in the Trigger Wizard, match up.

Here's the information on this direct from the MegaTune Manual:

Before tuning your advance table, be sure to use a timing light to verify that your 'trigger offset' is calibrated. Changing the Trigger Offset in MegaTune will not change the displayed advance, instead, it changes the actual advance as seen with a timing light. Your goal is to make these two match.

To do this, get your engine warmed-up (otherwise the timing moves as the temperature increases) and idling, then use a timing light to verify to be certain your actual advance as shown by a timing light equals your the advance display on the advance gauge in MegaTune. (8° in this case). (Note that positive numbers denote BTDC, and negative numbers denote after TDC.)

Image courtesy of Bowling and Grippo

Megatune PWM IAC Configuration:

• First open the MegaTune Configurator, and open CAR1>SETTINGS.INI>SETTINGS>IDLE_CONTROLLER and select PWM_GAUGE from the dropdown box at the top right.
• Save and exit the Configurator.
• Open MegaTune and connect to the ECU, and from the SETTINGS menu choose IDLE CONTROL.
• Select the PWM Warmup ‘Algorithm' and then you can configure the values for your vehicle and click ‘Burn to ECU'.
  

We do not have specific settings for all the Ford vehicles that you may be using this on.  For now, information on tuning these settings can be found in the MegaTune manual: http://www.megasquirt.info/megatune.htm#sd

Coolant (CLT) / Intake (IAT/MAT) Temperature Sensor Calibration

You can use your stock IAT and CLT sensors, and with the MegaSquirt-II you can calibrate these sensors through MegaTune.  It's best to leave the standard R4 and R7 'Bias Resistors' in place in the MegaSquirt and just configure this in the software.  You get better accuracy this way.

• Open MegaTune>Tools>Calibrate Thermistor Tables
• Select 'Coolant Temp Sensor', Select 'Fahrenheit', and enter these values:

• Click OK and the Coolant sensor will be calibrated.
• You're not quite finished yet though--- You need to repeat these steps, but choose 'Air Temperature' as the sensor table and use the same temp and resistance values from above as the sensors use the same curve.  This will calibrate the IAT as well.

NOTE-- Make sure you chose Fahrenheit or your readings will be WAY off with the above values....

More Information

• Everyone should thoroughly read the MegaManual.  I mean... you wouldn't buy a new doo-dad and install it without using the manual would you?  OK now seriously though... this is your pride and joy we're talking about here...  read the manual and the FAQ!!!   www.megasquirt.info
  • Read both the MS1 and MS2 sections, not all of the MS1 section will apply to you, but MUCH of it will, and the MS2 section isn't really complete without this information.
• Another great resource I refer to often is the MegaTune Tuning Software Manual-- here's the link:  http://www.megasquirt.info/megatune.htm

You shouldn't really 'need' this information, but it's linked here for further reading if you're interested.

• All TFI Mod information was sourced from here: http://www.megasquirt.info/ms2/TFI.htm

Using the Megasquirt-I and EEC-IV Adapter Harness with TFI

MegaSquirt-I PCBv2.2 Mods Required: 

• Input mod:  You install a 2k 1/4w resistor in place of D8
• Output mod: Run a jumper wire from the negative lead of LED 17 to pin 36 on the underside of the DB37 connector.  On V2.2 boards, there is no hole on the board, so you must solder the jumper directly to the DB37 connector lead.
• Fast idle mod: Replace transistor Q5 with a TIP120/121/122 power Darlington, as shown on our MK-PWMIAC catalog page.

MegaSquirt-I PCBv3.0 Mods Required: 

• Input mod:  You install a 2k 1/4w resistor in place of D2.  Jumper D1. Jumper TachSelect to OptoIn, XG1 to XG2, and TSEL to OptoOut.
• Output mod: Run a jumper wire from the top lead of D14 to the IGN jumper.
• Fast idle mods:
  • Remove Q20 and D8.
  • Remove R39 and install a jumper in its place.
  • Install a TIP120/121/122 in place of Q4. For more information, see our MK-PWMIAC page.
  • That's it!
• For fan control on a '94-'95, you can add a pair of relay control mod kits in the proto area. Their outputs wire to IAC1A for low speed fan control and IAC2A for high speed fan control.

MegaSquirt-I PCBv3.57 Mods Required: 

• Input mod:  You install a 2k 1/4w resistor between pins 2 and 3 of the JP1 main board jumper. Put jumper J1 in the 1-2 position, and connect the XG1-XG2 jumper.
• Output mod: Run a jumper wire from PAD1 to the center hole of Q16. Remove R58
• No fast idle mod is needed
• For fan control on a '94-'95, you can add a pair of relay control mod kits. Their outputs wire to IAC1A for low speed fan control and IAC2A for high speed fan control.

• Set Spark Output Inverted to Yes.
• Set Trigger Angle to 10 degrees.
• Set Dwell to Fixed Duty, and Spark Output Duty Cycle to 50% duty cycle. 
• Note: This is for the "Push start" modules, without computer controlled dwell.  The computer controlled dwell settings are not fully tested.