FlexFuel Switch (Dual Tables) for MicroSquirt

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Da GMan
MegaSquirt Newbie
Posts: 23
Joined: Mon Nov 25, 2013 3:12 pm

FlexFuel Switch (Dual Tables) for MicroSquirt

Post by Da GMan »

Hi Guys

Could anybody explain the flexfuel switch setup for the MicroSquirt please. I have read the manual and trialed it but it does not appear to behave as expected.

Manual says
when the FlexFuel pin is High, the dual table usage is set to VE1, AFRTGT1,
when the FlexFuel pin is pulled Low (grounded), the dual table usage is set to VE2, AFRTGT2.

I have 2 questions.

1. Must the switch have +12v and Earth and swich the Flexfuel cable between them or
Must the switch earth the FlexFuel line or not eath and leave it floating?


2. Once I have enabled FlexFuel Switch in TunerStudio all the tables in Tuner Studio are greyed out and you cannot use VEAL or edit any tables, to make any changes you need to disable the FlexFuel Switch, burn and then can choose to use, edit either Tables 1 or Tables 2 as chosen in the software. It that correct? I was thinking it would switch the tables in the software not disable all tables from editing. I guess this also brings up another question, can I switch on the fly or do i need to power off and restart the MicroSquirt.

I wanted to have 2 sets of tables, one for road use, normal cruising (economy) and a second for Rock Crawling, a little more aggresive and setup for when the rear muffler is removed.

Thanks
Microsquirt V3 - V3.83 - TunerStudio v2.6.14
Da GMan
MegaSquirt Newbie
Posts: 23
Joined: Mon Nov 25, 2013 3:12 pm

Re: FlexFuel Switch (Dual Tables) for MicroSquirt

Post by Da GMan »

Ok so what I have trialed so far.

FlexFuel wire floating or grounded (Not Game to try +12v unless told to do that)

This does appear to switch tables (Set table 2 very rich at idle and can see AFG gauge change when grounding pin 6 of the MicroSquirt)
It seems to be able to switch on the fly (No Reboot Required)
Unable to use TunerStudio to make changes with FlexFuel Switch enabled

Still a bit confused re the tables all being greyed out and having to disable the FlexFuel Switch in Tuner Studio, then select use Tables 1 or Tables 2 to make any changes to the Tables (VE and AFR) or use VEAL.

Is anyone else using this setup and is this behaviour correct? Am I going the correct way or is there another way to switch tables without a laptop?

Thanks
DonTZ125
Experienced Squirter
Posts: 337
Joined: Sat May 16, 2009 1:49 pm
Location: Scarborough, ON
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Re: FlexFuel Switch (Dual Tables) for MicroSquirt

Post by DonTZ125 »

I'm not going to comment on the behaviour of TS and the B&G code, but I will strongly recommend that you keep any 12v wires away from that pin! The FLEX pin has a pull-up resistor to +5v on the MicroSquirt PCB, so it really isn't floating.
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