DTC 07

Circuit Description:

The solar sensor is a reverse bias photodiode which measures sun load In
"automatic" mode the sun load sensor inputs data to the HVAC programmer on sun load conditions.

Test Description:

Number(s) below refer to circled number(s) on the diagnostic chart.

1. This test will determine if the sensor is providing correct data to the HVAC programmer.
2. This test will determine if a 5 volt reference is available to the sensor. If not, an open or short in CKT 590 or the programmer is at fault.
3. This test will determine if the sensor ground circuit is open.
4. This test will determine if a short to 5 volt reference is present in the ground circuit, causing an open Code 07 (no current flow).

Diagnostic Aids:

Bright sunlight will cause low counts and darkness will produce high counts, in parameter 04.

If no code is present after performing Step 4, an intermittent open or short is present. Enter parameter 00 and move the sensor harness and connectors to see if the code resets.