Table 2-1. Troubleshooting - Continued
TEST OR INSPECTION
Figure 2-45. Removal of HAND LAMP switch.
(9). Remove parts securing switch to the electrical control panel and remove.
(10). Install a new switch in the electronic control panel and secure with attaching parts.
(11). Connect and solder the electrical leads to the switch in accordance with the identification tags
on the leads.
TO avoid damaging the electrical connector, alternate tightening each of the two screws during reassembly.
(12). Install printed circuit board but do not tighten mounting screws. Connect the two electrical
connectors and secure by tightening two screws. Fasten ten screws that secure printed circuit to
(13). Place edge-lighted panel over connector, seat properly and secure with five mounting screws.
(14). Install BIAS control locking knob and BIAS knob on switch shaft. Secure BIAS knob by
(15). Install TEST SELECT knob on shaft with pointer at SOURCE VOLTAGE position. Install
MODE SELECT knob on shaft with pointer at GC position. Secure each knob by tightening
(16). Install electronic control panel assembly in case and secure with eight captive screws.
7. TEST METER FAILS TO INDICATE NULL WHEN BIAS CONTROLS ARE OPERATED
Step 1. Check for a defective GRU.
Replace existing GRU with a GRU that is operable, by disconnecting and connecting power cable (fig. 2-46).