Trim sender: 2-wire or 3-wire?

[HiWard]

VP SX-M transom assembly (serial no 4151128936, prod no 3869341). Drive is a DP-SM, engine is a 5.7GXi-HF

My trim gauge is intermittently displaying 56 and sounding a warning. I'm still able to tilt the drive up and down, engine starts regardless. This usually happens as I turn the key (before starting the engine) and will usually revert to displaying -4 with the drive fully down. It will also sometimes happen as I am underway, there is no specific pattern to the behaviour. This is the type of trim gauge on my boat:


Having searched this and other forums, I have concluded that the trim sender need replacing, preferably with a VP original. The sender to be replaced as two wires; brown/black and black. However, the wiring harness coming from the HIU (presumably) has threee wires; white/brown, red and black. My question is: should I buy a 2-wire or 3-wire sender? The 2-wire has obviously worked up until now and is slightly cheaper. Are they interchangable? What is the white wire for on the 3-wire sender?

 

[Scott Danforth]

the volvo penta drive manual has an entire section on troubleshooting and testing the trim system. go thru that. based on what you are describing, I would be leaning toward a flaky gauge or wiring, however I would do the troubleshooting to verify before spending money

 

[HiWard]

the volvo penta drive manual has an entire section on troubleshooting and testing the trim system. go thru that. based on what you are describing, I would be leaning toward a flaky gauge or wiring, however I would do the troubleshooting to verify before spending money

Would that be the "Sterndrive AC 2(2) Workshop Manual"?

 

[HiWard]

I looked in the document mentioned in my previous post and it does not contain much beyond removing and installing the sensor as well as measuring 11 Ohms between the two wires with the drive fully down.

My sender does not have the connector. The wires have been cut and spliced with butt connectors which are not marine grade. I will fix this and do some measurements while I'm at it. In the mean time, I'm still wondering what the difference between the 2-wire and 3-wire sensors is and if they are interchangable.

 

[dypcdiver]

Another point to beware of is that the senders for analogue and digital gauges are different.
Don't ask how I know that.

 

[Donald0039]

I would try and do as much diagnosis as I could by measuring resistance. And also measure while the drive is going up and down and see if it changes resistance nice and evenly or jumps around while changing resistance.

 

[HiWard]

I would try and do as much diagnosis as I could by measuring resistance. And also measure while the drive is going up and down and see if it changes resistance nice and evenly or jumps around while changing resistance.

Thank you , I'll do the measurements like you suggest.

 

[Jasun530]

My trim was working fine. My boat was work running well at the tilt switch on my dash went out. I am plugged it to replace it and I did. There was a bunch other wires on my dash since I’ve shorted and now I have no power to my dash in your power to make training the power to make you.

MOD EDIT: Please start your own thread, as it sounds like you have your own issue and adding it on to another person's thread is considered a hijack