Triggering alternate torque table

[marksawatsky]

On my LHU Ecotec, there are 4 different torque maps and the default map is Map A-Normal. There is also a Map B-Winter, Map C-Sport and a Reduced Power Map. Is there any ideas on how I would get the ECM to go into one of the other maps? It's a standalone application so I can't just push a sport button on the dash or anything like that. I am going to try triggering another map with the reverse pin on the ECM and the cruise control pin. There doesn't appear to be a pin on the ECM that relates to the maps in any way.
torque tables.PNG

[dertobi]

that won't work, the ECM gets a CAN signal from BCM which mode it should run in.
there are bit switches deeply hidden in the calibration (and non accessible with HPT) where you could change startup behavoir of ECM to directly be in mode B or C

[marksawatsky]

Can you think of a way to send a fake CAN signal to the ECM?

[codename Bil Doe]

If you are comfortable with Map A, copy it over to the other Maps. Regardless of reported conditions your driver demand shouldn't change.

[dertobi]

Can you think of a way to send a fake CAN signal to the ECM?

if you can figure out the correct message, of course, that should work.

but do you need that really in a standalone application?

the only thing you would need it for if you want to have switchable power modes with different peak power, thats what I use it for when the customer want's it, but i am not a friend of that sh**.

[marksawatsky]

I know what changing the map does and know that I can load a tune with the changes, but I want to change the map with a switch and not have to reload a tune. There are many advantages to this. If I have more than one map that can be accessed instantly, I can test two different maps back to back and see what is best. I can have an aggressive map for myself and a less aggressive one for my wife, who races the car also and there is no time between our runs to change tunes. I can have a map for asphalt and one for concrete to account for the difference in grip. I can have a dry map and a rain map. I can have one appropriate for sweeper intensive courses and one for slalom intensive courses. I contacted Vector North America because they make can-bus simulators and this is the response I got "We do have software that can simulate a module or an entire vehicle network. You do however, need to have proprietary files and information from GM to decode the data coming across the bus. The cost on our end for the software and hardware to do so would come in at roughly $14,000 if you are interested in only CAN communication." LOL $14,000!!!

[codename Bil Doe]

I got it now. Also beneficial in between runs if rain hits. If you don't find a solution electronically you could run dual switched ecu's. Would be more mechanical pita with splitting the wiring but is a last resort option.

[dertobi]

ok in that case it makes sense.
I could provide a link to a german company selling micro can gateway/simulators which would be 100% appropriate for this use, so you could utilize an analogue input switch and the unit sends a can signal according to switch position.
this is very easy programmable, the unit itself is around 100$ but software and programming cable/kit is round another 800$.
I already used this unit to simulate Immobilizers, wing or exhaust flap controls, and I also have a drag race car where I fitted a VW DSG trans to an Opel engine and doing a full VW rest bus simulation with an more advanced module to have the Trans running full standalone.
so it would just come down to figuring out the can message, but thats more than easy

[dertobi]

here we go I found it, in my documentations

should be canID 0x1F1 starting bit:38 length:2 values: 00= MAP A 01 = MAP B 11= MAP C

[marksawatsky]

That's interesting, do you have a link to the company that makes it? Does it plug into OBD2 port or the ECM directly?

[dertobi]

here you go:

https://www.mrs-electronic.de/en/pro...plc-can-4-ana/
you have to wire it directly, but if you're smart, of course you could wire it to an OBD plug

[marksawatsky]

That's great, thanks. I have a friend who designs efi systems for Holley, I'm going to see if he can set me up with something cheaper than the $900 USD this company wants.

[codename Bil Doe]

At that price the other option is a spare ecu or two. Takes 30 seconds to swap.