SMG Gauge Trim

[Atom2000]

I have a 2020 225hp with a SMG 04 gauge. The trim pointer on the gauge fluctuates randomly up and down without touching the trim switch. This happens when moving only, otherwise the gauge works fine if trimed but stopped. i.e it does not move up or down when the boat is stopped.. They replaced the sender and checked that the manual release valve is closed. but still the problem persists. Could it be some loose connection, defective or a bad ground somewhere. Where can i check for the grounds. Otherwise all other readings are in order. The smg 04 gauge is connected with a lowrance elite 7 and its trim gauge or dial reflects the smg gauge movement.so i think the gauge is working as it should. anybody had a similar issue. Thanks

[Moonlighter]

Sounds very much like a problem still with the trim sender or its connection.

I would start at the sender unit plug, and trace the wire back to where it connects to the main harness.

My main focus would be the plug itself and the wire connections to the plug. Undo it, check for loose or bent pins, loose or broken wires at the back of the plug. Then work your way along the wiring from there.

Trim data gets sent from the ecu to the SMG4 via the main harness along with all the other engine data, so chances are that the problem will be at the engine end, between the sender and the ecu.

[Atom2000]

Thanks will check