1992 Acura Legend I cant see how fast iM going!

ANDI12

MEMBER
1992 ACURA LEGEND

Electrical problem
1992 Acura Legend Front Wheel Drive Automatic 135xxx miles

Sometimes my speedometer goes crazy, Example- up to 100 and im only going 40 or sometimes its zero

Is this Even a Electrical Problem?

1 Reply

DAVE H

MECHANIC
13,384 POSTS

Speed sensor

Legend
Verify fuse No. 22 in underdash fuse block is okay. Speed sensor is located next to oil filter. Unplug 3-pin connector from speed sensor.
Using an ohmmeter, check for continuity between Green/White wire and ground. See Fig. 4. If continuity exists, go to next step. If continuity does not exist, repair open between speed sensor and ECU ground. ECU ground is located next to throttle body.
Fig. 4: Testing Vehicle Speed Sensor (Legend)
Courtesy of AMERICAN HONDA MOTOR CO, INC.
With ignition on, measure voltage between Black/Yellow wire and ground. If battery voltage is present, go to next step. If battery voltage is not present, repair open in Black/Yellow wire between speed sensor and underdash fuse box.
Measure voltage between Yellow/Red wire and ground. If voltage is about 5 volts, go to next step. If voltage is not about 5 volts, repair short to ground in Yellow/Red wire.
Reconnect wiring to speed sensor. Raise and support vehicle. Connect voltmeter between sensor connector Yellow/Red wire and ground. With ignition on and transaxle in Neutral, block one front wheel and slowly rotate other front wheel. Voltage should pulse between zero and 5 volts. If voltage does not pulse between zero and 5 volts, replace speed sensor.