User manual BENDIX ET-S SUSPENDED ELECTRON TREADLE

[. . . ] ® Bendix® ET- STM & ET-S2TM Suspended Electronic Treadle TREADLE MOUNTING PLATE POTENTIOMETER ACTUATOR BODY MOUNTING PLATE ACTUATOR BASE TREADLE PIVOT PIN CONNECTOR TREADLE TREADLE POTENTIOMETER MOUNTING PLATE ET-STM TREADLE ET-S2TM TREADLE DETROIT DIESEL CLOSED THROTTLE IDLE (OPEN) OPEN THROTTLE (FULL) 7 - 18% CATERPILLAR CUMMINS FIGURE 1 - ET-STM AND ET-S2TM ELECTRONIC TREADLES DESCRIPTION The ET-STM and ET-S2TM treadles are engine compartment bulkhead mounted electronic treadles. On electronically controlled diesel engines, the electronic treadle fulfills the same function as a conventional mechanical throttle. However, rather than transmitting a mechanical force to the engine governor, the electronic treadle controls engine speed by supplying a variable electrical voltage to the engine's electronic controller. The main components of the ET-STM and ET-S2TM treadles are: a mounting plate, suspended treadle, potentiometer (variable resistor), actuator body and base. [. . . ] Use suitable solvent to clean all metal parts (note that mineral spirits may damage the paint finish). Inspect the treadle and mounting plate for severe corrosion, pitting, or cracks. Superficial corrosion and/or pitting is acceptable. 3 3. Inspect the cable assembly for loose or frayed wires, physical damage, or any contaminants on the connectors. Replace as necessary. potentiometer clockwise until the first set of mounting holes align. Secure using two screws: torque to 25 (±5) in. (b) For Caterpillar Position Sensor: Aligning the drive slot, the position sensor engages the drive tang at the end of the drive shaft (see Figure 4). Rotate the position sensor clockwise until the first set of mounting holes align. Secure using two screws : torque to 20 (±2) in. Securely clamp the treadle mounting plate. (a) For Detroit Diesel Potentiometers: Align the drive slot, and engage the potentiometer the drive tang at the end of the drive shaft (see Figure 4). Rotate the DIGITAL VOLT/ OHM METER POWER SUPPLY (9-16 VDC) PIN C GROUND PIN B VOUT (OUTPUT) POTENTIOMETER PC. ON THIS SURFACE 300, 000 OHM RESISTOR TEST LOAD POTENTIOMETER Closed Throttle (open) Range: 7-18% Open Throttle (full) Range: 74-84% PIN A VREF (INPUT) FIGURE 6 - ELECTRICAL TEST SCHEMATIC FOR THE DETROIT DIESEL CONNECTOR Closed Throttle (open) Range: 10-20% Open Throttle (full) Range: 75-90% PIN A VREF (INPUT) 2000 OHM ±5% RESISTOR PEDAL POSITION SENSOR (PWM) . 001µF PIN B VOUT (OUTPUT) (CABLE) 47, 000 OHM ±5% RESISTOR PIN C GROUND Caterpillar output voltage is Pulse Width Modulated POSITION SENSOR FIGURE 7 - ELECTRICAL TEST SCHEMATIC FOR THE CATERPILLAR CONNECTOR 4 Closed Throttle (open) Range: 5-17% DIODES TEST LOAD 470 OHM TEST LOAD 470 OHM Vs SUPPLY VOLTAGE Open Throttle (full) Range: 70-81% LOCK TAB V3 (LOGIC HIGH AT IDLE) V2 (LOGIC LOW AT IDLE) IVS GROUND POTENTIOMETER SET VOLTAGE AND PC. SHOWN HERE PIN 6 IDLE VALIDATION SWITCH IVS PIN 2 PIN 1 PIN 5 PEDAL POSITION SENSOR PIN 3 PIN 4 TEST LOAD 47000 OHM . 01µ F Vs SUPPLY VOLTAGE V1 (OUTPUT) APS GROUND 4 APS GROUND 5 VS (INPUT) 6 (IVS) V3 LOCK TAB 3 V1 (OUTPUT) SIG1 1 IVS GROUND 2 (IVS) V 2 FIGURE 8 - ELECTRICAL TEST SCHEMATIC FOR THE CUMMINS CONNECTOR (c) For Cummins Potentiometers: Test 1: Where the set resistance and voltage is shown on a label. The Cummins potentiometer on the ET-STM and ET-S2TM treadle has an integral idle validation switch. It also has a set resistance value marked on the cover, which needs to be used to properly install the potentiometer. The drive slot in the potentiometer should engage with the drive tang at the end of the drive shaft. Next rotate the potentiometer until the hole in the metal sleeve matches the mounting holes on the actuator base. Loosely screw the potentiometer in place but do not tighten. Connect an ohmmeter to pins 3 (APS output) and 4 (APS ground) as shown in Figure 8. Now the installer should read the set resistance value marked on the label. Rotate the potentiometer until the ohmmeter reads the same resistance as shown on the label within ±10 Ohms. [. . . ] Secure with the nylon washer (4) and retaining ring (3). Make sure the ET-S2TM treadle has smooth, even treadle movement. Install the ET-S2TM treadle on the vehicle (see ET-STM & ET-S2TM Treadle Installation). ET-STM & ET-S2TM TREADLE INSTALLATION 1. Using the mounting hardware set aside, install the assembled electronic treadle on the vehicle. [. . . ]