Usage:
776C, 784B Tractors;
777C, 777D, 783B, 785B, 787B, 789B, 793B Trucks;
75 Challenger Agricultural Tractors.
- SUPPLEMENT: 12/11/95
Service Magazine; October 23, 1995; Page 22; "Dynamometer Testing Of Electronic Engines"
The list of machines in the Title of the article is not correct. The correct information follows.
776C, 784B Tractors; 777C, 785B, 789B, 793B Trucks; Challenger 75 Agricultural Tractors.
--------------- END SUPPLEMENT ---------------
When testing an electronic engine on a dynamometer, a 9X-9647 Throttle Position Sensor, and 8T-8697 ECAP / 7X-1412 T - Harness can be connected to the engine's ECM (Electronic Control Module). A 12 VDC power source must be connected, and can be supplied by a 12 Volt battery or other power supply of at least 10 Amps. The 12 VDC leads should be about 3 meters long in order to easily reach the power source. See illustration 1. See Chart 1 for parts list.
The production throttle position sensor on many production engines is powered by 8 VDC, supplied by the ECM. This production throttle position sensor supply line from the ECM should not be used to power the 9X-9647. The 9X-9647 requires 12 VDC. If you use the 9X-9647 Throttle Position Sensor in your dyno test setup, it will work with all electronic engines.
In order for the 9X-9647 Throttle Position Sensor to work correctly, it must be calibrated when the dynamometer test fixture is first set up. A mechanical stop must be installed so that the sensor signal duty cycle, which can be read on the ECAP (Electronic Control Analyzer and Programmer), is between 15 and 20 percent at low idle. The high idle stop should be adjusted so that the duty cycle is between 80 and 85 percent.
The remote mount Throttle Position Sensor calibration and adjustment procedures can be found in the Electronic Troubleshooting section of the engine's Service Manual. For example, the 3176B/3406E Engines are under procedure P-504 of SENR5582.
When an electronic engine is tested on a dynamometer with this throttle position sensor, some of the customer specified parameters may affect the way that the engine performs. If the engine does not perform as it should, check the customer specified parameters programmed into the ECM. Those parameters can be removed from the ECM, the engine can be tested, and the ECM reprogrammed to it's original configuration.
Illustration 1. Location of (1). 105-2081 Connector, (2). Red, positive lead to 12 volt power source, (3). Black, negative lead to 12 volt power source, (4). 8T-8732 Connector, (5). 8T-8736 Connector.
NOTE: The type of connector to attach to the ECM and pin locations in the connector will depend on the engine being tested. The connector and pin locations shown are those used on the ECMs of current production 3176B and 3406E Engines. For other engines, the parts manual and electrical schematic of the engine to be tested must be referenced to determine the correct connector part number and pin location. If you use the 9X9647 Throttle Position Sensor in your dyno test setup, it will work with all electronic engines.