OK, to confirm, the ultragauge is compatible with all 1996+ OBD II complaint vehicles, EXCEPT the few listed on their "exceptions" list. Sadly for you 1st gen guys, the 2001-2004 Tacoma is on that exceptions list
IF you have a 1st gen 6 LUG WITH ABS, then the ultragauge will work, however it is known to have conflicts with the ABS system during startup. UG does have a solution for this issue if your still interested. Remember, ONLY the 6 lug with ABS first gen is compatible, all other 1st gens. Cannot use the UG. See below for the "fix"
The 2001-2004 Tacoma with 6 lug wheels and optional ABS is compatible with UltraGauge. However, when the ignition is first switched on, the interaction with UltraGauge may cause the ABS system to become disabled and the ABS dash indicator will become lit. This issue was corrected by Toyota in 2005 and later years. This issue may exist on other 2000-2004 Toyota vehicles which have ABS.
The pre-2005 Toyotas use the 9141 protocol which uses pin 7 of the OBDII connector for communication, however, Toyota is apparently also using pins 14 and 6 of the OBDII connector for their own purposes. These pins are set aside by the OBDII standard for the CAN interface, and UltraGauge is connected to these pins. Many have found that isolating these pins will resolve the issue.
To isolate the pins we recommend one of the two options:
Cut the wires connected to pins 14 and 6 of the vehicle's female OBDII connector.* Add crimp-on bullet connectors to enable the cut wires to be connected and disconnected quickly and easily.* Place the male bullet connector on the wire end going to the OBDII connector.* When UltraGauge is attached, unconnect the wires
Purchase a short OBDII extension cable and carefully break off all of the unused male pins.* Such cables can be found for as low as $4 with a bit of searching.** To determine which pins are used, see the chart below.
The vehicle's female connector pinout:
*********** WARNING ****************
Pin 16 of the vehicles connector is always live. It is recommended to remove the associated fuse or disconnect the vehicle's battery when modifying connections.
Interfacefemale Connector Pins
The early Toyotas use ISO 9141 and pins 16,5,4,15 & 7.* All other pins, if present, are proprietary to Ford and are used only for diagnostic purposes.