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Code 2 - Vehicle Speed Sensor

  1. Block rear wheels and set parking brake. Raise front end of vehicle and support with stands. Connect ECU test harness connectors "A" and "B" between ECU and wiring harness connectors. See Figure . Turn ignition on.
  2. Slowly rotate left front wheel and measure voltage between ECU terminals A5 (pos.) and B8 (neg.). If voltage pulses from zero to 5 volts, proceed to step 5). If voltage does not pulse, turn ignition off and go to next step.
  3. Disconnect ECU harness connectors "A" and "B" from ECU side. Turn ignition on. Slowly rotate left front wheel and measure voltage between ECU terminals B7 (pos.) and A5 (neg.). Voltage should pulse from zero to 12 volts. If voltage pulses, substitute a known good ECU and recheck. If condition is rectified, replace original ECU. If voltage did not pulse, go to next step.
  4. If from step 3), voltage did not pulse from zero to 12 volts, repair open or short in White/Blue wire between ECU terminal A5 and VSS. If wires are okay, replace VSS.
  5. If from step 2), voltage pulses from zero to 5 volts, increase engine speed to 3000 RPM with no load. If code is reset, check No. 7 vacuum hose on vacuum manifold, and vacuum switch for leaks. If hose and switch are okay, substitute a known good ECU. If condition is rectified, replace original ECU.
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