Transmission Controls With PCM

Diagnostic Chart:

Wiring Diagram:

No VEHICLE SPEED SENSOR SIGNAL
DTC 41 indicates no vehicle speed signal pulses are present on circuit 400 at the PCM. Vehicle speed values are provided by the vehicle speed sensor. The sensor is a permanent magnet (PM) generator mounted on the differential area of the transaxle converter housing. The PM generator produces a pulsing voltage whenever vehicle speed is above 5 km/h (3 mph). These pulses occur 16 times per each revolution of the differential housing and are translated to provide vehicle speed in miles per hour. The km/h (mph) value read on the Scan tool Transmission Control Module (TCM) menu may very slightly from the ECM data or the speedometer.

DTC PARAMETERS
DTC 41 is set when the PCM has detected the following conditions after starting from a stop.
^ No vehicle speed. Vehicle speed = zero.
^ Turbine speed above 1400 rpm.
^ Steady moderate throttle.
^ Speed ratio across the torque converter is greater than 700 rpm.
^ During a 1-2 upshift the turbine speed pulls down by a one to two ratio. This diagnostic commands TCC off during a 1 to 2 shift.

TEST DESCRIPTION
Numbered steps below refer to steps on trouble chart.
1. This step verifies the problem is still present.
2. This test indicates if problem is PCM or a wiring/sensor problem.
3. An open or shorted sensor will set DTC 41. This test indicates if problem is a wiring problem or a faulty sensor.
4. An open ground or a short to voltage in circuits 400 or 401 will cause DTC 41 to set. This step indicates which circuit is faulty.

DIAGNOSTIC AIDS
When attempting to diagnose an intermittent problem use the Scan tool* to review supplemental diagnostic information. The supplemental data can be used to duplicate a problem.

*Select MALF History from Scan tool Transmission Control Module (TCM) menu.

Check the tightness of the female terminal grip with a spare male terminal.
^ Check wire routing for possible chafed wires.