Usage:
In January 1977, a new 5P6590 Wiring Harness Tester Group was released for use in place of the former 1P3550 Wiring Harness Tester Group, which was canceled. These testers are used to check electrical circuits on tandem-powered tractor-scrapers and off-highway trucks, and can be used during tests of power shift transmissions on the hydraulic test stand.
The 5P6590 Tester Group has several advantages over the 1P3550 Tester Group, including the use of separate test harness assemblies which connect to receptacles in the tester unit. This permits a wider range of test applications because different test harnesses can be connected directly to the tester, and replacement of a worn or damaged harness can be made without shipment of the complete tester group to the factory. Also, the new harness assemblies are more flexible and will give longer service life than those used in the 1P3550 Tester Group.
This design improvement can now be adapted to the earlier 1P3550 Tester Group. The development of a procedure to install the necessary receptacles in the earlier tester unit permits use of the later separate test harness assemblies. The complete procedure to make the conversion is available in a Special Instruction, Form SMHS7424.
