Page 167 - REPOWER REFERENCE GUIDE (2020)

Corrosion Protection

Shorted reference electrode circuit (to ground) 1 VDC

a - LED light
b b - Diagnostic pigtail
a

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The following chart describes the light functionality, and provides troubleshooting steps for the various LED light conditions:
MerCathode
LED Definition Possible Causes Summary of Fault Correction Possibilities
No fault ‑ controller
working properly. No action necessary ‑ this is normal LED light indication
Solid green Hull potential is N/A for a properly functioning MerCathode system.
between 0.84 and
1.04 V.
• Hull potential slightly below the 0.84 volt reading can
be common. Monitor over time.
• If the flashing sequence continues over time, then
perform the following:
• Loss of continuity • Measure hull potential by connecting the positive
Reference voltage between pod and lead of the multimeter to the controller pigtail, and
is below 0.84 V ground. the negative lead to the "–" post of the controller.
(This diagnostic • MerCathode
limit is based on reference wire or • Above reading can be verified by measuring
Outboard/ anode painted over. the hull potential with the service probe.
MerCruiser drives. • Check continuity connections between the trim tab
1 flash per 0.5 • Poor connection at and midsection plate.
second A reference voltage the "R" and "A"
below 0.84 V is not • Check continuity connections between the pod
necessarily a controller terminal. and vessel.
problem for a Zeus • Stagnant water near • Verify antifouling paint is not on the anode or
drive, a 0.7–0.75 V reference electrode. reference electrode.
is adequate • Sacrificial anodes
protection.) more than 50% • Operate engine for a few minutes, then turn off.
consumed. Check if reference voltage increases.
• Replace sacrificial anodes if more than 50%
consumed.
• Consult Mercury Technical Service if further review is
necessary.

90-8M0149179 eng NOVEMBER 2018 © 2019 Mercury Marine Page 6D-5