As a rule of thumb:
* GM cars and light trucks use SAE J1850 VPW (Variable Pulse Width Modulation).
* Chrysler products and all European and most Asian imports use ISO 9141 circuitry.
*
Fords use SAE J1850 PWM (Pulse Width Modulation) communication patterns.
J1850 PWM--The connector should have metallic contacts in pins 2, 4, 5, 10, and 16.