Switch Contacts Become Tarnished
Usage:
EXCAVATORS301.5 (3YW1-UP),
302.5 (4AZ1-UP) MINI HYDRAULIC EXCAVATORS
302.5 (4AZ1-UP) MINI HYDRAULIC EXCAVATORS
THIS TIB REPLACES THE OCTOBER 6, 1999 EXCAVATOR TIB, "SWITCH CONTACTS BECOME TARNISHED." DESTROY THE OCTOBER 6, 1999. IT WILL NOT APPEAR IN THE SEMI-ANNUAL INDEX.
Problem:
The contacts in the 156-6679 Switch or 176-1517 Switch become tarnished causing a high resistance to the flow of electricity, an open circuit. The 156-6679 Switch or 176-1517 Switch may cause one of the following symptoms:
- A. The engine may not start because the switch will not close.
- B. When the machine is running and the consoles are in the down position, there will be no hydraulic power for the machine.
Solution:
Clean the switch contacts or replace the switch.
Cleaning Procedure
- 1. Disconnect the switch from the harness. Remove the switch.
- 2. Connect the switch to a high load (resistance) circuit such as a 12 volt battery and a work light.
- 3. Use the switch to turn the work light on and off. If the switch does not function properly, replace the switch.
- 4. Install the switch in the machine.
COPYRIGHT 1999 CATERPILLAR ALL RIGHTS RESERVED
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