Electronics - Heat Control; Electronics - Power Failure - GE PANDA Service Manual

Chapter 4: Troubleshooting
Troubleshooting Tables
4.4.11 Electronics – Heat Control
4.4.11.1 Heat Engine Failure
Possible Causes
No signal from Heat
Control Processor
4.4.12 Electronics – Power Failure
4.4.12.1 Unit Will Not Turn On (Power Fail Alarm)
Possible Causes
No 12V DC power
supply
Blown fuse on
Power PCA
No AC voltage to
Power PCA
4-42
Step Troubleshooting Procedure
Refer to section "4.4.5.13 Sys Fail 11 [AA AA AA AA]"
1.
for information.
Step Troubleshooting Procedure
Remove the rear cover. Using a DC Volt Meter,
check the voltage from chassis to the top of fuse,
1.
F7, on the Power PCA. If 12V is present, skip to
Step 5. Otherwise, continue.
Check the connection from the power supply to
2. the Power PCA (J20). Make sure the connector and
pins are properly seated.
If OK, remove the connector, J20, on the Power
3. PCA. Using a DC Volt Meter, check for 12V at
pins 1,5 on the cable side.
4. If there is still no DC, skip to Step 8.
Using a DC Volt Meter, check the voltage from
chassis to the bottom side of fuses F7 (12V) and
5. F8 (3.5V). If there is no voltage, continue with steps,
to find/correct the short before replacing the
fuse(s).
Disconnect J22 on the Power PCA. Test for power-
to-ground short on the Control PCA by probing the
6.
harness connector: Pin 1, 2 (BLK) Ground; Pin 3
(RED) 3.5V; Pin 4 (ORN) 12V.
Isolate location of short: Disconnect the ribbon
cable from the Control PCA to the Alarm/ Light
7. PCA; Disconnect the flat flex cable from the Control
PCA to the LCD Module. Replace the PCA or module
that contains the short.
*Assuming that the unit is plugged into the wall
and the rear main switch is turned On* Turn on
the front panel switch. Disconnect J28 from the
8.
Power PCA and test at pins 2,5 (center pins). If
there is no AC voltage, continue with steps. If OK,
then proceed to Step 10.
Comments
Comments
DC Power SpO
2
warmer harness
part #:
6600-1587-700
Service Manual