GEMS Diff Controller for Subaru N11

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Gerald81
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GEMS Diff Controller for Subaru N11

Post by Gerald81 » Sat Aug 06, 2011 3:51 am

I'm interested in installing the GEMS differential controller for a 2007 STI, but am wondering if the GEMS unit use inputs from the steering angle sensor found on the 06/07 STI? Also is the installation a plug and play affair?

Many thanks in avance!

R!C0
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Re: GEMS Diff Controller for Subaru N11

Post by R!C0 » Mon Aug 08, 2011 1:54 pm

Hi Gerald,

Steering angle is not taken into consideration. Control is based on wheel speed, handbrake, footbrake and throttle position.
Manual: http://www.gems.co.uk/assets/Media/down ... anual.pdf?
The unit is plug and play, but does need to be fitted into a factory case, so we require a donor factory EMCD unit.

HTH

Rico

Gerald81
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Re: GEMS Diff Controller for Subaru N11

Post by Gerald81 » Sat Aug 27, 2011 8:43 pm

Hi Rico,

Another question I have is, will the controller interface with my speedo cluster to dynamically display the actual lock amount while driving in the active modes?

Regards,
Gerald

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Re: GEMS Diff Controller for Subaru N11

Post by Gerald81 » Mon Aug 29, 2011 10:19 am

Just installed the controller in my 2007 STI but my ABS light and parking brake lights (dimmed) are now lit when driving. Will the unit work with the factory ABS system?

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Re: GEMS Diff Controller for Subaru N11

Post by R!C0 » Tue Aug 30, 2011 12:44 pm

Yes the unit should work with the standard ABS unit. Sounds like it could be a problem with the CAN. Do you have copy of the calibration in the EMCD you could send?

Thanks

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Re: GEMS Diff Controller for Subaru N11

Post by Gerald81 » Tue Aug 30, 2011 1:36 pm

I retrieved the ABS error codes and they were 47 (improper CAN communication), 29 (any one of four ABS wheel speed sensors) and 56 (longitudinal g sensor).

I am unable to provide the calibration in the EMCD right now as I have not bought a serial-to-USB cable yet, but it was basically the map that was pre-loaded with the GEMS unit. When I was using the factory DCCD controller previously, I had no such warnings, both the factory DCCD and ABS were working fine.

Gerald81
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Re: GEMS Diff Controller for Subaru N11

Post by Gerald81 » Tue Aug 30, 2011 4:00 pm

Hi Rico, I've retrieved and sent you the calibration file via PM. Please let me know what's wrong, thanks.

Gerald81
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Re: GEMS Diff Controller for Subaru N11

Post by Gerald81 » Mon Sep 05, 2011 4:32 am

Further to the ABS issue, I have a couple of other questions on the Subaru EMCD:

1) How do I get live data (eg. individual wheel speeds, EMCD amps) to be displayed in GWV4 while connected to the EMCD? My Telemetry menu appears to be disabled.

2) I undestand from the user manual that the Footbrake regime is active when the brake lights are on, and the handbrake is off. However, it is also stated that diff lock under the Footbrake regime will only be applied "if higher than the value from the active tables". What does this mean?

Regards,
Gerald

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Re: GEMS Diff Controller for Subaru N11

Post by R!C0 » Mon Sep 05, 2011 10:59 am

1) You can view live values by looking at parameters: View > Parameters. This gives you access to all the current values like wheel speed, demand etc.

2) This is referring to the active maps Map1A etc, which are the main control maps. This will be referred to unless overridden by the Fbrake table.

HTH

Gerald81
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Re: GEMS Diff Controller for Subaru N11

Post by Gerald81 » Mon Sep 05, 2011 11:20 am

Thanks for that, will give it a try. The footbrake regime does not seem to be working for me (i.e. it does not appear to override my active accel and decel maps) but I will test it further. Do you have any tips on how I can set the car up for trail braking if I wish to lock the diff when braking in a straight line, but unlock it when I start turning while continuing to apply slight braking pressure?

Can you also confirm that the measurement of "slip" is defined as the difference between the average front wheel speed and average rear wheel speed in kph, which is defined by the RPMSTEP value?

Also do you have any solutions or advice regarding the ABS issue I'm experiencing? Many thanks.

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Re: GEMS Diff Controller for Subaru N11

Post by R!C0 » Mon Sep 05, 2011 5:09 pm

I need to check these with one of our engineers here, please bear with me...

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Re: GEMS Diff Controller for Subaru N11

Post by Gerald81 » Mon Sep 05, 2011 5:13 pm

I understand, thanks Rico. I've just sent you a PM regarding the wheel speeds (they are reading 0 kph throughout which is why my maps aren't working as I thought they would), including a copy of my current calibration. Would appreciate if you could advise on that as well, thanks!

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Re: GEMS Diff Controller for Subaru N11

Post by Gerald81 » Tue Sep 06, 2011 3:44 am

Just an update, I changed the wheel teeth parameter from "43" (as recommended in the user manual) to "0" and now the wheel speed display appears to be work correctly.

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Re: GEMS Diff Controller for Subaru N11

Post by R!C0 » Wed Sep 07, 2011 5:40 pm

From speaking to our engineer here, its basically an application problem. The EMCD was designed for the 2L version of the Impreza without the electronic throttle. Hence the CAN information to and from the unit looks to be different on your car - which I believe is the 2.5L version.

Our engineer here has been speaking to Terence (who I believe was your supplier?), in supplying a version with CAN transmit turned off which could help with the ABS problems.

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