Allison MD 3070PT User Manual

TS2470EN
Printed in the U.S.A. Copyright © 1998 General Motors Corp.
Troubleshooting
Manual
Division of General Motors Corporation
P.O. Box 894 Indianapolis, Indiana 46206-0894
May 1998
Revision 1, 199910
Allison Transmission
MD/HD/B Series Transmissions
WTEC II Controls
(Pre-TransID and TID 1)
MD 3060/MD 3066/MD 3560(P)(R)
MD 3070PT
HD 4060/HD 4560(P)(R)
B 300/B 400/ B 500(P)(R)

Allison MD 3070PT Specifications

General

Impedance	600 Ohms
Polar Pattern	Cardioid
Connector	XLR
Color	Black
Type	Dynamic
Dimensions	180 mm x 50 mm

Summary

SECTION 4 — WIRE CHECK PROCEDURES

Checking for Opens and Shorts

Details procedures for checking wires for opens, shorts between wires, and shorts-to-ground.

Transmission Connector and Internal Harness Checks

SECTION 6 — DIAGNOSTIC CODES

Understanding Diagnostic Codes

Covers code memory, reading/clearing, responses, displays, and lists.

Troubleshooting Diagnostic Codes

Guides on starting troubleshooting, solenoid locations, and schematic interpretation.

CODE 13 XX — ECU INPUT VOLTAGE

Troubleshooting ECU Input Voltage Issues

Details common causes for low/high ECU input voltage and troubleshooting steps.

CODE 14 XX — OIL LEVEL SENSOR

Troubleshooting Oil Level Sensor Failures

Guides on diagnosing faulty wiring, OLS, or ECU related to Code 14 12.

CODE 21 XX — THROTTLE POSITION SENSOR FAULT OR ADJUSTMENT

Troubleshooting TPS Faults and Adjustments

Covers TPS issues, linkage, wiring, and ECU calibration for Code 21 XX.

CODE 22 XX — SPEED SENSOR/CIRCUITRY FAULT

Troubleshooting Speed Sensor and Circuitry Issues

Guides on checking sensor integrity, wiring, and replacement for Code 22 XX.

CODE 23 XX — SHIFT SELECTOR

Troubleshooting Shift Selector Issues

Guides on checking connections, wiring, and replacing the shift selector for Code 23 XX.

CODE 24 XX — SUMP FLUID TEMPERATURE

Troubleshooting Sump Fluid Temperature Issues

Covers diagnosing cold or hot fluid temperatures and related ECU/sensor problems.

CODE 25 XX — OUTPUT SPEED SENSOR, DETECTED AT ZERO SPEED, X RANGE

Troubleshooting Output Speed Sensor Zero Speed Faults

Guides on checking fluid level, codes, sensors, and clutch pressures for Code 25 XX.

CODE 32 XX — C3 PRESSURE SWITCH

Troubleshooting C3 Pressure Switch Issues

Covers checking C3 pressure switch circuit for opens, shorts, and resistance.

CODE 33 XX — SUMP OIL TEMPERATURE SENSOR

Troubleshooting Sump Oil Temperature Sensor Issues

Guides on checking sensor resistance, wiring, and ECU for Code 33 XX.

CODE 34 XX — EEPROM COMPATIBILITY OR CHECKSUM FAULT

Troubleshooting EEPROM Calibration Issues

Guides on reprogramming EEPROM or replacing ECU for calibration faults.

CODE 35 XX — POWER INTERRUPTION

Troubleshooting ECU Power Interruption

Covers causes of power loss like switch sequencing, ground connections, and ECU replacement.

CODE 41 XX — OPEN OR SHORT-TO-GROUND IN SOLENOID CIRCUIT

Troubleshooting Solenoid Circuit Opens/Shorts

Guides on checking solenoid circuits for open or short-to-ground conditions.

CODE 42 XX — SHORT-TO-BATTERY IN SOLENOID CIRCUIT

Troubleshooting Solenoid Short-to-Battery Circuits

Guides on diagnosing short-to-battery conditions in solenoid wiring and circuits.

CODE 43 XX — SOLENOID LOW SIDE CIRCUIT, OPEN DRIVER, OR WIRE SHORTED-TO-GROUND

Troubleshooting Solenoid Low Side Circuit Faults

Covers diagnosing open drivers or shorts-to-ground in solenoid low-side circuits.

CODE 44 XX — SHORT-TO-GROUND IN SOLENOID CIRCUIT

Troubleshooting Solenoid Short-to-Ground Circuits

Guides on diagnosing short-to-ground faults in solenoid wiring and circuits.

CODE 45 XX — OPEN CONDITION IN SOLENOID CIRCUIT

Troubleshooting Solenoid Circuit Open Conditions

Guides on diagnosing open circuits in solenoid wiring and coils.

CODE 51 XX — OFFGOING RATIO TEST DURING SHIFT (TIE-UP TEST)

Troubleshooting Offgoing Ratio Test Failures

Guides on diagnosing issues with offgoing clutch release and ratio tests.

CODE 52 XX — OFFGOING C3 PRESSURE SWITCH TEST DURING SHIFT

Troubleshooting C3 Pressure Switch Test Failures

Covers diagnosing C3 pressure switch issues and related hydraulic problems.

CODE 53 XX — OFFGOING SPEED TEST (DURING SHIFT)

Troubleshooting Offgoing Speed Test Failures

CODE 54 XX — ONCOMING RATIO TEST (AFTER SHIFT)

Troubleshooting Oncoming Ratio Test Failures

CODE 55 XX — ONCOMING C3 PRESSURE SWITCH (AFTER SHIFT)

Troubleshooting Oncoming C3 Pressure Switch Issues

CODE 56 XX — RANGE VERIFICATION RATIO TEST (BETWEEN SHIFTS)

Troubleshooting Range Verification Ratio Tests

CODE 57 XX — RANGE VERIFICATION C3 PRESSURE TEST (BETWEEN SHIFTS)

Troubleshooting C3 Pressure Switch Range Verification

CODE 61 XX — RETARDER FLUID HOT

Troubleshooting Retarder Over-Temperature Conditions

CODE 62 XX — RETARDER TEMPERATURE SENSOR

Troubleshooting Retarder Temperature Sensor Issues

CODE 64 XX — RETARDER MODULATION REQUEST DEVICE FAULT

Troubleshooting Retarder Modulation Request Device

CODE 69 XX — ECU MALFUNCTION

Troubleshooting ECU Malfunctions

Details ECU malfunctions like open drivers, timeouts, and checksum errors.

SECTION 8 — GENERAL TROUBLESHOOTING OF PERFORMANCE COMPLAINTS

Initial General Checks

Lists essential pre-troubleshooting checks before diagnosing specific vehicle or transmission issues.

Retarder Performance Complaints

Range Clutch Slippage and Chatter