shortage of outputs.

[Residence1]

currently in the process of revamping my harness i built for my mkiv supra (6 cylinder) i have a few questions....

i opted to utilize the spare low side ignition, low side injector, and Peek/hold injector outputs for future expansion of fueling (secondary injectors). problem i am possibly seeing is that while doing so, it doesn't leave any outputs available to control my electronic boost solenoid (3 port). is there a work around for this? i do have a C125 display/logger with I/O unlocked. maybe use one of the 4 outputs of the C125?

second question.... i may of stumbled upon the answer in a previous thread but it is for a m400 but i am thinknig it will still hold true here.

does 5vA (pin A02) have to go to 0VA (Pin B15) and 5VB (Pin A09) have to go to 0VB (pin B16) or are the 0V pins (B15, B16) bused together internally?

[David Ferguson]

You should review I/O configuration (M1 Tune Menu - Tools->Edit Input/Output Resources...), to make sure that you haven't assigned one of the ouputs to something you aren't actually using.

You didn't mention the Half-Bridge outputs, these can also be used for the Turbocharger Bypass Actuator Output Resource. Try configuring that and it will show available resources that can be used.

You could add an E816 expander, but I would suggest, you may want to consider selling your ECU and purchasing a model with more I/O. If you have an M130, the M150 has two connectors that are compatible with the M130 connectors so your harness could be used unmodified, and the additional I/O coming from the other connectors.

[Stephen Dean]

As David suggested, changing from an M130 (if you currently have one) to an M150 will provide a lot more I/O, and your current Package will migrate across. If you sell the M130, you could potentially change to the M150 for around the same cost as the E816.

Have a look through the Firmware Wiring (Help | Firmware Wiring...) data, and see if there are any free outputs, or if there are outputs allocated to functions that are not being used, such as the Half Bridges.

I wouldn't recommend using the C125 as a Boost controller. It is possible to do, but the outputs on the dash are only capable of driving 500mA combined, and usually a MAC valve needs more than that. You also loose out on a lot of the boost control functionality and protections that are in place in the M1 if you use the C125 instead.

You do not have to have sensors that are wired to 5VA using 0VA, but it is recommended to do this, so that the M1 can cope with a sensor that pulls the 5V rail down, or pushes the 0V up and then affects the other sensors wired to the same supplies. If you have a sensor that is connected to A and B, then it may be that the sensors output is influenced in a manner that results in an incorrect reading if the M! applies a ratiometric change to the voltage read on the pin.

[Calibrated_Dan]

If you're still running the standard IAC you could also look at moving over to DBW, it only uses one bridge output instead of 2 and opens up a whole extra level of tuning.

It does require 3 more AV inputs though to accommodate the Throttle Servo Position Main & Tracking and the Throttle Pedal Main & Tracking. But would open up a full bridge of two half bridge outputs.

We've got a project here in the UK launching soon that's got DBW, 8 Speed Auto [fully controlled by the M1] and Cruise Control on an M1 ECU on a 1993 Supra - the options really are endless with M1!

Daniel @ Calibrated Performance