SeaDoo Speedometer sensor fix instructions

[BrianMoore]

In your post #39, you said you were getting voltage changes when you spun the wheel. Doesn't that prove the magnets are activating the Hall switch? The 3.5 VDC seemed off to me. When I tested mine twice with 2 sets of components, the low voltage was very close to the 5.6VDC of the zener. But who knows if I fixed mine since I haven't had it out on the water.

 

[Darrellnbay]

I was getting those values, but when I connected my sensor to the speedometer it didn't seem to activate the speedometer. I will need to assemble my components kn my bench to do another test. Using the same paddle wheel. I'll try to do this on the weekend.

 

[BrianMoore]

Got it out on the water couple days ago. My issue changed but didn’t go away. Before speedometer worked consistently from 0 to around 20 then would cut out and go to zero. Now it doesn’t like 0 to 10 most of the time. It likes to start working at 10. Works to about 25 then cuts out and goes to 10. Well this is in general. It has fits where it will work at higher speeds and lower speed as it used to. Still seems more of a poor connections somewhere.

I now realize that I lied when I had said I had pulled the connectors apart and cleaned them. I did the one for the pickup. Looking at the wiring diagram, I didn’t do the one by the speedo. There is a purple and black wire connector that jumps over from the oil/fuel indicator under the cover underneath the hood. I took it apart and it looked good to me. However it had dielectric grease in it. I think all the other connectors I have taken apart have been dry so I think someone else may have been looking at the same issue in the past. The purple yellow wire has no connector and runs all the way to the MPEM. I didn’t take that apart in since I could mess up something else in the big connector.

Rebuilding the pickup was a fun project for me. I am not sure if I will pursue trying to fix or replace anything else. The fun part of riding a jetski is riding, not staring at the speedometer.

 

[etemplet]

I've been cleaning up a bit and sometimes I run across sensors and parts I have. I believe I have 4 or 5 of each of the electronic components to repair the speedos as well. If/when I come across them again anyone that wants them is welcome to them if you are going to use the parts for repairs. Someone may have already asked but that was a long time ago.

2 things I can't believe about the sensors. (1) that they sell broken ones for $25 and (2) that I've seen that stupid little pick up wheel for $25 being sold all by itself.

I like the OEM pick up because to me it is more reliable when working properly but I have bought (2) GPS pick ups from Candoo. It's not about needing a speedometer to me but I like to get everything on the ski working as it should. Good Luck All !!

 

[etemplet]

On a side note, I'm surprised that I was able to get the sensor and speedo working on the Speedster. Usually the sensor is bad. Happily it was corroded wiring in the plug. I was actually shocked it worked. We'll see if it remains working. I'm not used to these Seadoos being nice to me.

 

[69DartGT]

I've been cleaning up a bit and sometimes I run across sensors and parts I have. I believe I have 4 or 5 of each of the electronic components to repair the speedos as well. If/when I come across them again anyone that wants them is welcome to them if you are going to use the parts for repairs. Someone may have already asked but that was a long time ago.

2 things I can't believe about the sensors. (1) that they sell broken ones for $25 and (2) that I've seen that stupid little pick up wheel for $25 being sold all by itself.

I like the OEM pick up because to me it is more reliable when working properly but I have bought (2) GPS pick ups from Candoo. It's not about needing a speedometer to me but I like to get everything on the ski working as it should. Good Luck All !!

Hey, I would take any of the sensors and parts if you are just going to get rid of them.

 

[69DartGT]

Got it out on the water couple days ago. My issue changed but didn’t go away. Before speedometer worked consistently from 0 to around 20 then would cut out and go to zero. Now it doesn’t like 0 to 10 most of the time. It likes to start working at 10. Works to about 25 then cuts out and goes to 10. Well this is in general. It has fits where it will work at higher speeds and lower speed as it used to. Still seems more of a poor connections somewhere.

I now realize that I lied when I had said I had pulled the connectors apart and cleaned them. I did the one for the pickup. Looking at the wiring diagram, I didn’t do the one by the speedo. There is a purple and black wire connector that jumps over from the oil/fuel indicator under the cover underneath the hood. I took it apart and it looked good to me. However it had dielectric grease in it. I think all the other connectors I have taken apart have been dry so I think someone else may have been looking at the same issue in the past. The purple yellow wire has no connector and runs all the way to the MPEM. I didn’t take that apart in since I could mess up something else in the big connector.

Rebuilding the pickup was a fun project for me. I am not sure if I will pursue trying to fix or replace anything else. The fun part of riding a jetski is riding, not staring at the speedometer.

I have not had either one on the water yet, hopefully in the next couple of weeks. Then I guess I will see if the fix worked for me.

 

[BrianMoore]

“I like to get everything on the ski working as it should.” I worked Mechanical/Hydraulic commercial airplane factory functional tests for the last few decades of my career. They assured that the planes were assembled and rigged correctly. Finding pushed back/bent pins, cut wires, crap relays, bad components, etc. could be challenging and I really loved that part of my job. And we never scrapped a multi-million dollar plane because we couldn’t find the cause. When I said oh well guess the GTI speedometer isn’t going to work, it has been eating at me ever since.

I did spend some time yesterday checking grounds because I really had no plan. Today I started looking at wiring diagrams. I really wish I had some functional descriptions so I understand how these gauges function. But I have an idea now of what is the most likely suspect.

The GSX has pretty much the same speedometer and actually has labeling on the schematic. Purple and Black are power and ground to the gauges. Purple /Yellow is speed signal. Pink is fuel signal. Blue is oil signal. GSX has power and ground going first to the speedometer and then feeds those to the Info Center. GTI has power and ground going to the oil/fuel gauge first and then feeds it to the speedometer. My oil/fuel gauge is working with none if the intermittent stuff I see in the speedometer so the power and ground is making it that far steadily. I think chances are that the oil/fuel gauge power and ground feed though is most likely fine since that should be a simple solder connection. I looked at the power ground connector to the speedometer and it looked clean and good to me. To be sure I should measure that connector with a meter so I know it is coming through the oil/fuel gauge. It would be nice to know what voltage I am looking for. I also need to look in the big connector on the MPEM to see what the Purple/Yellow pins look like. If I can’t find anything, then it is the speedometer itself.

Does this seem like a reasonable plan? Any other ideas or experiences that would be helpful?

 

[69DartGT]

“I like to get everything on the ski working as it should.” I worked Mechanical/Hydraulic commercial airplane factory functional tests for the last few decades of my career. They assured that the planes were assembled and rigged correctly. Finding pushed back/bent pins, cut wires, crap relays, bad components, etc. could be challenging and I really loved that part of my job. And we never scrapped a multi-million dollar plane because we couldn’t find the cause. When I said oh well guess the GTI speedometer isn’t going to work, it has been eating at me ever since.

I did spend some time yesterday checking grounds because I really had no plan. Today I started looking at wiring diagrams. I really wish I had some functional descriptions so I understand how these gauges function. But I have an idea now of what is the most likely suspect.

The GSX has pretty much the same speedometer and actually has labeling on the schematic. Purple and Black are power and ground to the gauges. Purple /Yellow is speed signal. Pink is fuel signal. Blue is oil signal. GSX has power and ground going first to the speedometer and then feeds those to the Info Center. GTI has power and ground going to the oil/fuel gauge first and then feeds it to the speedometer. My oil/fuel gauge is working with none if the intermittent stuff I see in the speedometer so the power and ground is making it that far steadily. I think chances are that the oil/fuel gauge power and ground feed though is most likely fine since that should be a simple solder connection. I looked at the power ground connector to the speedometer and it looked clean and good to me. To be sure I should measure that connector with a meter so I know it is coming through the oil/fuel gauge. It would be nice to know what voltage I am looking for. I also need to look in the big connector on the MPEM to see what the Purple/Yellow pins look like. If I can’t find anything, then it is the speedometer itself.

Does this seem like a reasonable plan? Any other ideas or experiences that would be helpful?

Sounds like you had a very interesting career, I would have loved to do something like that. As far as your speedo problem, it sounds like you are on the right track. I would check every connection and then probably move on to the speedo itself. Let us know what you find, I am curious now.

 

[BrianMoore]

I did enough testing to convince myself it isn’t a connector issue. I took the MPEM connector off and it looked brand new inside. Sure enough it started sprinkling when the connector was off. I sprayed some contact cleaner, put a little dielectric grease on the pins and put it back together before it got wet. Battery was 12.35 V. Power to the speedometer was 10.85 V. Ground back to the battery or to the engine was 1.7 Ω key off and 83 Ω key on. Resistance from power to ground through the speedometer was 123kΩ. Resistance from power to ground through the oil/fuel gauge was 199Ω. I really don’t know what that means since the wires were connected to the MPEM and I don’t know what is going on inside that.

Mostly I wiggled and jiggled wires between the gauges and the computer to see if any readings jumped. They all stayed rock steady. 10.85 V and a few Ohms on the ground don’t worry me. Digital switches aren’t perfect like an open/close mechanical switch. With the erratic behavior of the speedometer and no erratic behavior in the wiring and a newly rebuilt speed sensor, I am thinking it is the speedometer.

Has anyone ever taken a speedometer apart? I am imagining it is some wires going to circuit board but getting down to that point may mean destroying the speedometer. And once I get in there, all I’ll be able to do is look for bad solder joints since I have zero electronic aptitude.

 

[69DartGT]

I did enough testing to convince myself it isn’t a connector issue. I took the MPEM connector off and it looked brand new inside. Sure enough it started sprinkling when the connector was off. I sprayed some contact cleaner, put a little dielectric grease on the pins and put it back together before it got wet. Battery was 12.35 V. Power to the speedometer was 10.85 V. Ground back to the battery or to the engine was 1.7 Ω key off and 83 Ω key on. Resistance from power to ground through the speedometer was 123kΩ. Resistance from power to ground through the oil/fuel gauge was 199Ω. I really don’t know what that means since the wires were connected to the MPEM and I don’t know what is going on inside that.

Mostly I wiggled and jiggled wires between the gauges and the computer to see if any readings jumped. They all stayed rock steady. 10.85 V and a few Ohms on the ground don’t worry me. Digital switches aren’t perfect like an open/close mechanical switch. With the erratic behavior of the speedometer and no erratic behavior in the wiring and a newly rebuilt speed sensor, I am thinking it is the speedometer.

Has anyone ever taken a speedometer apart? I am imagining it is some wires going to circuit board but getting down to that point may mean destroying the speedometer. And once I get in there, all I’ll be able to do is look for bad solder joints since I have zero electronic aptitude.

Just a thought, did you ever use a regulated steady stream of compressed air to spin the paddle wheel to see if it spins up without chattering? And see what the speedo reads testing it that way. One of the paddle wheels on a sensor I was messing with wobbled and chattered so bad that I couldn't get it to read right. I put some grease on it and it smoothed out and the readings were better. To fix the issue on that sensor I am going to upsize the little shaft the paddle wheel rides on because I think it is wore a little. If that makes sense?