VSS Help

AZ98TRD · 04-27-2012, 06:57 PM

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Scuba · 04-27-2012, 08:36 PM

Look up Tacodell's thread on the Dakota install.

AZ98TRD · 04-28-2012, 05:42 PM

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06tacov8 · 05-30-2012, 10:45 PM

MFC connector, pin 15. Should be a PPL/WHT wire. That is the VSS feed back to the engine ECU. Only problem is that it may not be the same PPM (pulses per mile) as the VSS signal to the cluster. I seem to remember it being different but I don't have those notes handy right now. After you hook it up, check the VSS PID on a scan tool. If it is in the ballpark you are good. If it is wildly off then you will need a converter that provides 2 different speed ratio outputs (one for speedo one for ECU).

A couple notes to be aware of:

1. in the absence of this signal the ecu is using the OSS (output shaft speed sensor) to look up shift points, but the VSS input is the PRIMARY input for shift points so they can and probably will change slightly once you hook it up.

2. once this is connected the cruise control in the engine ecu should be enabled again.

3. the VSS signal you are deriving from the OSS with the Dakota converter is not correct when in low range, unlike the factory signal from the ABS ecu. Therefore if the Dakota module doesn't allow switching to a second conversion ratio when in 4LO and you hook this up you may get unpredictable shifting (like really, really early upshifts). Just something to watch out for. BTW, the 4LO signal is on the MFC connector pin 7 (should be L.GRN/YEL wire) and its grounded in 4LO.

Next time, just ask...

04-27-2012, 06:57 PM	#1
AZ98TRD Veteran Member Join Date: Aug 2010 Location: Phoenix, Az Posts: 671	VSS Help ... __________________ 1998 Tacoma TRD AWD. Lexus 4.7L 2UZ-FE. Lexus A750F 5 Speed Auto. SOLD... 2006 4Runner SR5 4WD. 4.0L V6 1GR-FE. 5 Spd Auto A750F. Bilstein 5100 w/ OME 884 (FRT). Bilstein 5100 w/ OME 895E (REAR). 285/70/17 Nitto Terra Grapplers. BOVADS roof rack. Unitrol Siren w/ Code 3 100w speaker. Last edited by AZ98TRD; 05-30-2012 at 11:19 PM.

04-27-2012, 08:36 PM	#2
Scuba Veteran Member Join Date: Feb 2009 Location: CREEDMOOR SPORTS, Anniston, Alabama Posts: 7,732	Look up Tacodell's thread on the Dakota install. __________________ 99 Single Cab 2.7. Awaiting 3 Link SAS.

04-28-2012, 05:42 PM	#3
AZ98TRD Veteran Member Join Date: Aug 2010 Location: Phoenix, Az Posts: 671	... __________________ 1998 Tacoma TRD AWD. Lexus 4.7L 2UZ-FE. Lexus A750F 5 Speed Auto. SOLD... 2006 4Runner SR5 4WD. 4.0L V6 1GR-FE. 5 Spd Auto A750F. Bilstein 5100 w/ OME 884 (FRT). Bilstein 5100 w/ OME 895E (REAR). 285/70/17 Nitto Terra Grapplers. BOVADS roof rack. Unitrol Siren w/ Code 3 100w speaker. Last edited by AZ98TRD; 05-30-2012 at 11:20 PM.

05-30-2012, 10:45 PM	#4
06tacov8 Member Join Date: Sep 2007 Location: Sunny Arizona Posts: 30	MFC connector, pin 15. Should be a PPL/WHT wire. That is the VSS feed back to the engine ECU. Only problem is that it may not be the same PPM (pulses per mile) as the VSS signal to the cluster. I seem to remember it being different but I don't have those notes handy right now. After you hook it up, check the VSS PID on a scan tool. If it is in the ballpark you are good. If it is wildly off then you will need a converter that provides 2 different speed ratio outputs (one for speedo one for ECU). A couple notes to be aware of: 1. in the absence of this signal the ecu is using the OSS (output shaft speed sensor) to look up shift points, but the VSS input is the PRIMARY input for shift points so they can and probably will change slightly once you hook it up. 2. once this is connected the cruise control in the engine ecu should be enabled again. 3. the VSS signal you are deriving from the OSS with the Dakota converter is not correct when in low range, unlike the factory signal from the ABS ecu. Therefore if the Dakota module doesn't allow switching to a second conversion ratio when in 4LO and you hook this up you may get unpredictable shifting (like really, really early upshifts). Just something to watch out for. BTW, the 4LO signal is on the MFC connector pin 7 (should be L.GRN/YEL wire) and its grounded in 4LO. Next time, just ask... __________________ 2006 TRD Sport DC Prerunner Lexus 3UZ-FE V8, Lexus A650E 5-speed auto, stock limited slip, Lexus electronic variable assist steering, S&S Lexus tri-Y headers, true duals w/ Magnaflow, custom Lexus interior trim (wood steering wheel and shift knob, 10 way power heated leather seats with memory, auto climate control), Toyota power antenna, orange LED cupholder lights, white LED bed lights, various mods (fog lamp, dash brightness, map light, inverter anytime, extra power outlets, etc etc). Last edited by 06tacov8; 05-31-2012 at 09:49 PM.

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