Toyota Tacoma 2001-2004 with ABS


(The solution options below apply to other vehicles as well)

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 2000-2007 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.   If your vehicle has pins 7 and pins 6 &14 loaded, then you may have this issue.

To isolate the pins we recommend one of two options:


Purchase the ISO-9141 & KWP Isolation cable

Cut the wires connected to pins 14 and 6 of the vehicle's female OBDII connector.  Done.. or optionally 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.  These wires are only necessary if you plan to take your vehicle to the dealer where a proprietary manufacturer specific scan tool would be attached to the OBDII.

The vehicle's female connector pinout:
Female OBDII connector pin out image

*********** 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.


Interface female Connector Pins
J1850-VPM 2
Early Ford 2,10
ISO 9141 7,15
CAN 6,14
KWP2000 7,15
Common pins:
Battery +12VDC 16
Ground 5,4

The early Toyotas use ISO 9141.  All vehicles which use ISO 9141 use pins 16,5,4,15 & 7.  All other pins, if present, are proprietary and are used only for diagnostic purposes.