EN – 72
Also see Figure 168.
c. Position the black probe on the engine block.
d. Turn ignition key to ON position.
e. Turn the potentiometer from low-idle to full throttle.
Voltage to the red wire should measure 4.90 V DC – 5.0 V
DC at both low-idle and full throttle positions.
Verify system ground by moving black probe to blk/wht wire
(pin 4) while key is on. Compare to previous voltage
readings. Any drop in voltage is likely a ground issue.
If voltage measures less than 4.9 V DC, replace ECU.
3.
With a multi-meter, measure the V DC of the
green / white wire. See Figure 169.
a. With engine off, position the red probe on the
terminal of the green / white wire.
b. Position the black probe on the engine block.
c. Turn ignition key to ON position.
d. Turn the potentiometer from low-idle to full throttle.
Voltage to the green / white wire should measure close to
0.01 V DC at low-idle and close to 5.0 V DC at full throttle.
If voltage does not vary between low-idle and
full throttle, there is an open connection in the harness.
Replace the harness.
Fluttering Servo Motor
If the throttle plate in the throttle body flutters continuously
when the key is in the ON position, check the following:
1.
Wire harness connection to the ECU.
a. With the ignition key in the off position, disconnect
the wire harness from the ECU and inspect
connection at the tan, purple and yellow wires on
the 12-pin connector. See Figure 161. If
connection is faulty, repair, if possible. If repair
cannot be completed, replace the throttle body.
b. If connection is good, a faulty connection exists in
the throttle body or servo motor. Replace the
throttle body.
Figure 168
Figure 169
