Trim Gauge Not Working

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Updated on April 2, 2022

Trim gauges are essential for proper functioning of your boat. If your boat’s trim gauge isn’t working right, it could be impossible to make full use of its installed motor. 

When the trim gauge of a boat fails to work, it may be due to a slight glitch or more serious problem. It’s better to consult an experienced technician if you don’t know how to fix a trim gauge that’s not working. 

However, it’s not an indication that you can’t try something to fix your boat’s trim gauge. Tips in this guide could prove useful to get your boat’s trim gauge in great shape again. 

Why is My Power Trim Gauge Not Working?

A boat’s power trim gauge may stop working if there is inadequate or no supply of power to its motor. In most cases, a bad solenoid (magnetic coil around an iron wire), corrosion, or failed relays could be the cause too. 

Most trim system failures are commonly linked to electrical issues and disconnections. Sometimes, the hydraulic pump assembly in a boat could be the cause of a failed trim gauge. 

How to Check Trim Gauge

The steps below are best suited to check trim gauges of Evinrude, Johnson, Force, OMC, 4-Stroke Suzuki, and Yamaha engines. If your engine brand isn’t listed above, make sure it has a compatible trim sender.

And it’s a great idea to consult a qualified technician to help you check the trim gauge if you can’t. It’s better to pay for professional assistance than ruin your boat’s trim gauge or worse. 

Step 1: Power the gauge

Power up the trim gauge of your boat by connecting a positive line to its ‘I’ terminal and an earth wire to its ‘G’ terminal. Make sure these two wires are the ONLY ones connected to your trim gauge. 

Step 2: Connect and short sending terminal

After connecting these wires, some outboards will read at full UP while others might read as full DOWN. Next, short the sending terminal at your gauge to an earth position and the outboard pointer will change direction. 

Note that this process may not be applicable to outboard engines made by brands like Nissan, Chrysler, and Tohatsu. Also, trim senders might not be available from most engine brands and should be purchased separately. 

How to Adjust Trim Gauge

Step 1: Turn on boat

Turn your boat on by switching its key to its ‘ON’ position. Next, raise your motor up to see its trim sending unit. 

Step 2: Loosen screws on trim sending unit

Next, loosen screws on your boat’s trim sending unit so that you can easily move its positioning slots. Move the positioning slots a little just to be sure you can. 

Step 3: Lower motor to ‘full DOWN’ position

The next step involves lowering your motor to its full DOWN position. Setting the motor to a full DOWN position makes it easy to tweak the trim gauge needle. 

Step 4: Check trim needle

Check where your motor’s trim needle is positioned when placed at a full DOWN position. Repeat all the steps above while tweaking the needle to ensure it aligns with your motor’s current position. 

Next, tighten screws on your boat’s trim sending unit to complete adjustments. Properly-adjusted trim needles will normally go up from your down trim marker whenever you trim your boat.

How Does a Trim Gauge Work? 

Trim gauges work to display the tilt or trim angle of your boat’s outdrive or outboard unit. 

Some trim gauges may come from OEM manufacturers and fit many engines. Other trim senders may be specialized in design and work on some specific engines and fail in different models. 

How to Troubleshoot Trim Gauge

You can troubleshoot the trim gauge of your boat’s motor by inspecting its wiring for any problems. Next, check the gauge to make sure it is operational if there are no signs of corrosion or breakage in its wiring. 

Why is My Trim Gauge Stuck in Up Position?

The wiring between a gauge and sender may have been disconnected for your boat’s trim gauge to stay at full UP. In other cases, faulty adjustments on your trim gauge sending unit may cause a full UP position. 

In other cases, a power wire might be grounded out, loose, corroded, or broken.

Setting your trim gauge with the correct connectors is a smart way to solve the full UP problem. If you don’t have a clue about how to fix this issue, it’s best to contact a qualified boat technician to help. 

How to Fix Trim Gauge Stuck in Up Position

The best way to fix a trim gauge stuck in full UP position will be to replace it. However, some advanced issues may be undetectable without experience and might require professional help. 

The other way to fix a trim gauge stuck in UP position will be to carry out a full inspection of your current unit. A disconnected wire might cause your trim gauge to remain in a full UP position.