Last season had continual problem with "no compass" and /or "no heading" alarm message on ST 70. Raymarine certified tech diagnosed as computer problem, so the computer was sent back to Raymarine for servicing. Well the problem persists. Now I'm wondering if 1) misdiagnosed, or 2) could a cell phone in close proximity be interfering with fluxgate compass?
I have enclosed the compass test to confirm a good working fluxgate in the system.
Multi-meter should be set to:
(a) Resistance scale
(b) 200 ohm scale
The following procedure should then be followed:
1. Disconnect the transducer from the system.
2. Connect one multi-meter lead to the red wire and the other lead to the green wire and a reading as indicated in the test data table should be present.
3. Follow the above procedure for all the color combinations indicated in the test data table.
4. If all readings match those indicated assume the compass transducer is functioning correctly.
Compass Test Data:
Red to Green - 4 ohms
Red to Yellow - 4 ohms
Green to Yellow - 8 ohms
Screen to Blue - 8 ohms
All other combinations - OPEN
You are looking for a short or open. A +or - 2 Ohm reading is allowed.
If this check indicates a fault with the compass then you will be best served by replacing the compass. If no problem is indicated then you should send the compass and the course computer to a repair facility for evaluation.
Hi, I´m having problems with, apparently; the compass. I did the tests you suggested and my readings were 6 and 6.1 instead of 4 ohms, and 9.6 or so instead of 8 ohms, all the rest open as you mentioned. May I assume that the compass is working and the problem could be in the course computer? Thanks