MoTeC Global Forum

I seem to have a problem with the gear detection.
Can anyone help me figure out what is being set wrong.
Thanks

Is the speed sensor measuring wheel or tailshaft speed. Do you have logging?
Do you have the speedometer gear ratio for the tailshaft to sensor turns ratio?

Hi

I believe you must have 4.58 on dif gear ratio.

AF

Make sure TC/LC is on as well, you don't have to set up TC/LC and use it, just turn it on.

Thanks for the help.

Blu302: I currently do not have logging until I get my CDL3.
And I believe the speed sensor is measuring the shaft.
"speedometer gear ratio for the tailshaft to sensor turns ratio"
Is it this one?
Speedometer gear ratio
(driven/drive)
I am not sure about that as it says not applicable.
However, I do find the ratio for the 5 speed, 28/36.

I am wondering if only the 5 speed uses the speedometer gear for the sensor, and 6 speed uses other method to measure the drive speed.

Arve Flaat: I tried entering 4.58 as the diff ratio and the gear just jumped to 6.

Scott@FP: You mean the traction control and the launch control are on? I do not have the advance function yet.

Thanks,
Anthony

OK. For some reason I seem to recall speed related calcs stop if you have TC/LC and you turn it off as they are handled internally by the TC/LC routines.

Speed sensor (OEM VSS) is more or less on the WHEEL in this app, not tailshaft and then reduced by diff ratio. Speedo gear ratio is accounted for in Dig Input Setup in the pulses per km or mile. It is not 4 pulses per wheel rev, but 4 pulses per VSS revolution. Just set up your Dig Input on Speed in your preferred km/hr or mph format as described, I think KM/h ends up being in the 410 range for stock diameter tires. Now, with that being said, for gear ratio cal since its on the WHEEL speed and not tailshaft you need to multiply each primary gear gear ratio by the final drive ratio then enter that in the gear ratio field, and leave final drive at 1.0, so 1st gear is 2.909 x 4.583 = 13.33. If the trans also has a primary reduction ratio (EVO does not) you would need to enter it in the total gear ratio calc as well.

okay, so I should try having all the gear ratio multiply the diff gear which is 4.583, leave the diff gear as 1?
what about the TC/and LC? have the TC set to 1 (ground speed vs. drive speed)?

and also, I am using Dig1 as input from OEM EVO 9 Vehicle Speed Sensor as User channel 1 with custom calibration in km/h, and they seem to be correct.

You don't need to use up a User Channel if you don't want to, but you DO have to set up one of the Drive Speed channels under the Sensor/setup/speed tab. In your case set up both drive speeds as User 1, 1 to 1, and it should work. Heck set up all 4 drive/ground speeds, not going to matter unless you use TC as gnd vs drive speed, and you need them if you use gnd or drv speed as an axis in a table. Normally you would set them up as an input from Dig1-4 whichever is the VSS input, and as 1 to 1, and the Dig input setup is already calibrated for either KM/H or MPH.

A quick and dirty way to set up the Dig Input calibration is to drive at a constant speed say 60 KM/H, then adjust the dig input/parameters/calibration number until the displayed Drive Speed matches the speedo reading of 60.

I will be getting the CDL3 kit with GPS so I will have that for the ground speed.
For drive speed I will wait till I get the MDC.

I will test out the setup tomorrow and let you know the result. Your information is much appreciated.

Thanks,
Anthony

MDC its even easier, all 4 individual wheel speeds get bussed over on the RS232 as KM/H, just set up your 4 wheel speeds as ECU2_1 thru 4, 1 to 1. Your choice as to whether you call the fronts or backs Drive or Ground.
In addition you can use the other MDC data as well, here's the list-