Reatta V6-231 3.8L VIN C SFI (1990)
Data Circuit
CIRCUIT DESCRIPTION:
When the ECC communication are lost, service diagnostics usually cannot be entered but a quick scan of the panel will usually help isolate the source of
the fault. The ECC panel is powered by ignition. If the power source is lost the panel will usually display a segment check. Loss of serial data will result
in three ashes being shown on the panel VF display. This indicates power and ground are OK. If the panel displays normal outside or interior set
temperature, power, ground, and serial communications are being received thus panel replacement is indicated.
TEST DESCRIPTION: Numbers below refer to circled numbers on the diagnostic chart.
1.
This step checks for power and ground to the panel. Voltage should be "HI" for both power to ground checks.
2.
This step checks for serial data voltage. Normal voltage should be above 1.0 volt and varying. A steady voltage indicates a second open exists, or
the ALDL cover is off.
