Riviera V6-231 3.8L VIN C SFI (1989)
Picture Circuit
CIRCUIT DESCRIPTION:
Because we have a picture on the screen, we know the CRT has power, ground, wake-up, video, vertical sync, and horizontal sync signals.
TEST DESCRIPTION: Numbers below refer to circled numbers on diagnostic chart.
1.
The summary page will appear first when the key is turned "ON." Since diagnostics cannot be accessed, pressing the Metric switch on the IPC will
verify the BCM's ability to listen to or hear the messages from the other devices on the data line. Viewing the temperature display on the CRT will
indicate if the BCM is OK, if the display changes from °F to °C.
2.
Connecting the tester to the CRT, with the CRT removed, will verify the integrity of the CRT. If the red light on the tester never lights, or if the
CRT beeps continuously, or never beeps, replace the CRT.
3.
When the tester was connected to only the CRT, the CRT was OK if the tester lit up the CRT, followed by 3.0 green lights on the tester, when the
CRT screen dimmed and brightened followed by a fourth green light and a double BEEP. Moving the tester to the harness at the CRTC and noting
tester lights and BEEPs; the problem can be narrowed down to the faulty circuit or CRTC.