Home/
Registry/
Ford/
Bronco/
1992-1996/
“Buckin Bronco”/
Photo
supermotors.net/registry/media/1116048
Ford 4R70W Transmission Wiring Diagram - MLP, TPS, ECT Sensor to PCM (Page 29-4)
Wiring diagram for the 4R70W transmission showing the manual lever position sensor, throttle position sensor and PCM circuits with color-coded wires.
This document is page 29-4 of a Ford factory wiring diagram set covering the 4R70W automatic transmission, uploaded as one page of a multi-page series for a 1996 Ford Bronco. The diagram shows the sensor inputs to the Powertrain Control Module (PCM) used for transmission control. It details the Manual Lever Position (MLP) sensor circuit (positions P, R, N, D, 1, 2), fed by circuit 359 GY/R from splice S146 via connector C1012, with output circuit 199 LB/Y to PCM pin 30 and circuit 766 BK/LG to PCM pin 29; switch testing is referenced on page 149-10. Explanatory callouts state the MLP sensor is a step-down resistor voltage divider used for desired gear and EPC pressure, and that it houses the START and BACKUP lamp circuits. Also shown are the Engine Coolant Temperature (ECT) sensor (circuit 354 LG/R through C183 and C101 to PCM pin 7, used for torque converter clutch scheduling), the Throttle Position Sensor (circuit 355 GY/W through C185, C101 and C1024 to PCM pin 47, used for EPC pressure and shift/TCC scheduling), and the A/C-heater input (circuit 883 PK/LB to PCM pin 10, used for EPC pressure under engine load). Cross-references point to pages 24-4, 24-5, 24-7, 29-3, and 54-2.
Is this accurate? Sign in to help verify it.
Frequently asked questions
- What does the Manual Lever Position (MLP) sensor do on the 4R70W transmission?
- Per the diagram's callout, the MLP sensor uses a series of step-down resistors acting as a voltage divider; the PCM monitors the voltage corresponding to the manual lever position to determine desired gear and EPC pressure. The sensor also houses the START circuits (allowing starting only in PARK or NEUTRAL) and the BACKUP lamp circuits, which close in reverse.
- What wire colors and circuits connect the MLP sensor to the PCM?
- Circuit 359 GY/R feeds the MLP sensor from splice S146 through connector C1012; circuit 199 LB/Y runs from the sensor through C1012 and C103 to PCM pin 30, and circuit 766 BK/LG goes to PCM pin 29. Circuit 970 DG/W connects to PCM pin 5.
- What is the ECT sensor input used for in transmission control?
- The Engine Coolant Temperature (ECT) sensor, wired on circuit 354 LG/R through connectors C183 and C101 to PCM pin 7, is used in determining Torque Converter Clutch Scheduling.
- Which PCM pin does the Throttle Position Sensor connect to and why?
- The TPS connects on circuit 355 GY/W through connectors C185, C101 and C1024 to PCM pin 47. It is used by the PCM in determining EPC pressure, shift, and Torque Converter Clutch scheduling.
- What is the 883 PK/LB wire at PCM pin 10 for?
- Circuit 883 PK/LB at PCM pin 10 comes from the Air Conditioner/Heater system (page 54-2) and is used in determining EPC pressure during increases in engine load.
No comments yet.