Bunn TU3 service manual Ing Diagrams and check the wiring harness, ON/OFF Switch

SERVICE (cont.)	If voltage is not present as described, refer to the Wir-
ON/OFF SWITCH (SELECTOR SWITCH - OPTIONAL)	ing Diagrams and check the wiring harness.

P1187.40

FIG. 16 ON/OFF SWITCH

Location:

The ON/OFF switch is located in the front of the hood, above and to the left of the brew funnel.

Test Procedure:

Brewers W/Out Half Batch Option

1.Disconnect the brewer from the power source.

2.Remove the black and white/violet wires from the switch terminals.

3.With a voltmeter, check the voltage across the black wire removed from the ON/OFF switch and the white wire remaining on the switch terminal.

4.Connect the brewer to the power source. The in- dication must be 120 volts ac for two wire 120 volt models.

5.Disconnect the brewer from the power source.

If voltage is present as described, proceed to #6.

6.Check for continuity across the center and end terminals of the top row when the switch is in the ÒONÓ position.

If continuity is present as described, replace the wires, the switch is operating properly.

If continuity is not present as described, replace the switch.

Brewers W/Half Batch Option

1.Disconnect the brewer from the power source.

2.Remove the black wire from the top center switch terminal.

3.With a voltmeter, check the voltage across the black wire removed from the selector switch and the white wire or red wire on the tank heater.

4.Connect the brewer to the power source. The in- dication must be:

a) 120 volts ac for two wire 120 volt models.

a)240 volts ac for two wire 240 volt models.

b)100 volts ac for two wire 100 volt models.

5.Disconnect the brewer from the power source.

If voltage is present as described, proceed to #6.

If voltage is not present as described, refer to the Wir- ing Diagrams and check the wiring harness.

6.Check for continuity across the center and left or right terminals of the top row when the switch is in the ÒFULL" or "HALFÓ position.

If continuity is present as described, replace the wires, the switch is operating properly.

If continuity is not present as described, replace the switch.

7.Disconnect the pink and gray wires from the left and center terminals.

8.Check for continuity across the left and center ter- minals in rows two, three and four with the switch in the half batch position.

If continuity is present as described, replace the wires the switch is operating properly.

If continuity is not present as described, replace the switch.

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