Trim goes down but only goes up with Trailer button not when using up switch

CayugaCobalt

Petty Officer 3rd Class
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May 6, 2008
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1997 Cobalt 233 with 7.4 L and Bravo 3

As stated in message title, trim will go down but only goes up with Trailer button. Should I focus on "up switch" in shifter handle or is there an up relay or solenoid that I need to replace? When I hit up button NOTHING happens.
 

tpenfield

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Jul 18, 2011
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Most likely, it is the trim limit switch that is located on the port side of the outdrive. Often the wires become frayed and the 'switch' no longer works.

The limit switch prevents one from raising the outdrive beyond the safe limit with the regular trim switch. Thereafter, the trailer switch must be used.
 

khe

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Dec 7, 2012
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Inspect the wiring on the port side sender - many times the wires rot from water intrusion into the wiring. Both the trim limit and trim indicator sensors are replaced at the same time. To test the limit sender, lower the drive, then unplug the trim limit sender wiring from the trim pump in the engine compartment. Using an ohm meter, check for continuity across the wires that lead to the limit sender. You should have continuity (close to zero ohms) if the sender is good. If it reads infinite, there is an open in the wiring to the trim limit sender - most likely a broken/rotted wire near the gimbal assembly.

The symptoms are a textbook case of broken trim limit sender wires.
 

gm280

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Jun 26, 2011
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OR a trim switch or the wires from that switch at the helm to the engine. Nothing ruled out yet. JMHO
 

CayugaCobalt

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Thanks all, I will check the wires as recommended. Does anyone know if this limit switch can be replaced on this boat without removing drive unit? I have heard it is sometimes possible.
 

stonyloam

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It is pretty easy to isolate the problem. Go to the stern, you will find two black wires from the trim limit going into two connectors, one with a purple/ white wire and one with two blue/white wires. Unplug the black wires and with a piece of insulated wire, jumper between the two connectors. Try the trim switch. If it works then your helm switch is OK and the problem is in your trim limit circuit. Check the black wires for physical damage. If they look OK you may be able to disassemble the limit switch and clean it. Make sure you mark it so you can put it back together correctly. Or leave it jumpered, just be careful because there will be no limit.
 

tpenfield

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Thanks all, I will check the wires as recommended. Does anyone know if this limit switch can be replaced on this boat without removing drive unit? I have heard it is sometimes possible.

I have done the switch/wiring replacement on both Bravo 1 and Bravo 3 outdrives without removing/disassembling stuff. it is a bit tricky, but if you get the drive all the way down, there is enough room to sneak in a 1/4" drive socket wrench extension to reach the retaining bolt that holds the wire grommets.

You may have to un-bolt the trim cylinder rams in order to get the drive down far enough.
 

CayugaCobalt

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May 6, 2008
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Thanks Stonyloam and tpenfield! Was busy polishing and waxing most the weekend. Initial inspection of wires at switch is they don't look bad from the outside.
 

w3bexec

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Apr 10, 2017
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1997 Cobalt 233 with 7.4 L and Bravo 3

As stated in message title, trim will go down but only goes up with Trailer button. Should I focus on "up switch" in shifter handle or is there an up relay or solenoid that I need to replace? When I hit up button NOTHING happens.


I had this same exact issue on my Alpha 1 last week. It stopped working right after I "bumped" the ground with the outdrive when lowering it after parking it. I'm not sure about the Bravo but the Alpha has grease zerks on the trim limit and trim send switches.I might have been overzealous with the grease or a little bit of grease was knocked into it when I bumped. Thanks to another forum I found that sometimes some grease will get onto the copper plates(?) where the contacts rest (sorry I don't know the true terminology for these). The trim up is closest to where the grease could leak in, so it makes sense. I took the cover plate off and gently removed the contact bar and insert that it rests on (it just sits on a pin) and sure enough, it was coated in grease. I cleaned up the contacts and plates and lightly sanded it those. Put it back together and... nothing... didn't work. More searching and it turns out I did not put the contacts back in the exact proper position, the contacts were not aligned right. I had to go through the trim limit alignment instructions that are part of the instructions for replacing the switch. Fairly simple but an in and out of the boat multiple times to adjusting trim to check measurements if your doing it without a helper. Make a mark ofwhere the contact bar is before removing to prevent having to do that. Hope this helps someone.
 
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