2003 XPDI Help!!

[watwood1]

Hello everyone,

I have a 2003 XPDI that keeps blowing the battery fuse as soon as I get the DESS key close to the post. The Seadoo was operating fine until I pulled the key to cut if off and then started blowing fuses when I went to attach it.

I have disconnected the VTS module and the LCD connector on the MPEM and neither made any difference.

Any suggestions on what might be happening? Thanks for your help.

 

[Sportster-2001-951C-Stock]

The term "battery fuse" makes me think of the 30A fuse in the e-box where the coils are, is this the one you're referring to?

If that's the case, obviously there's a short somewhere on the other side of the MPEM, probably need to keep disconnecting stuff till the short disappears, how about the fuel pump?

There are quite a few engine components in the #4 connector on the MPEM, injectors and the fuel pump are in that one and a couple other engine sensors.

Connector #2 has the stator rectifier in it, but the DESS is also in that one so probably have to disconnect the rectifier separately else by disconnecting #2 the MPEM won't see the DESS.

 

[watwood1]

The term "battery fuse" makes me think of the 30A fuse in the e-box where the coils are, is this the one you're referring to?

If that's the case, obviously there's a short somewhere on the other side of the MPEM, probably need to keep disconnecting stuff till the short disappears, how about the fuel pump?

There are quite a few engine components in the #4 connector on the MPEM, injectors and the fuel pump are in that one and a couple other engine sensors.

Connector #2 has the stator rectifier in it, but the DESS is also in that one so probably have to disconnect the rectifier separately else by disconnecting #2 the MPEM won't see the DESS.

Thanks for the response. It is the 25 amp battery fuse located on the MPEM. Does that change your diagnosis?

 

[Sportster-2001-951C-Stock]

Thanks for the response. It is the 25 amp battery fuse located on the MPEM. Does that change your diagnosis?

Helps narrow it down, yes. I'm looking at the schematic here and see the BATT fuse feeds 5 other fuses, only one of which is the same size, the REG fuse is 25A, so I'd say pull the REG fuse and then see if the BATT fuse still blows. I don't have a DETAILED schematic of the inside of the MPEM so it's still a process of elimination. If pulling the REG fuse gets everything back up, then the problem seems to be in the rectifier circuit or possibly in the MPEM itself but I can't say that with 100% certainty b/c according to the diagram the current has nowhere else to go but through smaller fuses.

So my diagnosis based on what I see is the problem is most likely in the rectifier circuit, could be a damaged stator or a shorted rectifier. The only way to know is to either unplug the rectifier or yank the REG fuse, if either of these choices eliminates the symptom of the BATT fuse blowing then I'd pursue diagnostic measurements in the rectifier circuit.

In order to conserve 25A fuses(maybe your stock is becoming depleted by now), you should be able to go with a smaller fuse for testing purposes, 15 or 20A, preferably the 20A size.

So, pull the rectifier connector(preferable, IMO) or rectifier fuse out of the circuit and give it another try, hopefully the short goes away and you can concentrate on the charging circuit and eliminate the MPEM itself as a potential cause.

 

[Coastiejoe]

Helps narrow it down, yes. I'm looking at the schematic here and see the BATT fuse feeds 5 other fuses, only one of which is the same size, the REG fuse is 25A, so I'd say pull the REG fuse and then see if the BATT fuse still blows. I don't have a DETAILED schematic of the inside of the MPEM so it's still a process of elimination. If pulling the REG fuse gets everything back up, then the problem seems to be in the rectifier circuit or possibly in the MPEM itself but I can't say that with 100% certainty b/c according to the diagram the current has nowhere else to go but through smaller fuses.

So my diagnosis based on what I see is the problem is most likely in the rectifier circuit, could be a damaged stator or a shorted rectifier. The only way to know is to either unplug the rectifier or yank the REG fuse, if either of these choices eliminates the symptom of the BATT fuse blowing then I'd pursue diagnostic measurements in the rectifier circuit.

In order to conserve 25A fuses(maybe your stock is becoming depleted by now), you should be able to go with a smaller fuse for testing purposes, 15 or 20A, preferably the 20A size.

So, pull the rectifier connector(preferable, IMO) or rectifier fuse out of the circuit and give it another try, hopefully the short goes away and you can concentrate on the charging circuit and eliminate the MPEM itself as a potential cause.

I think this is very good advice. You should be able to isolate what circuit the issue is on and then go from there.

 

[watwood1]

Helps narrow it down, yes. I'm looking at the schematic here and see the BATT fuse feeds 5 other fuses, only one of which is the same size, the REG fuse is 25A, so I'd say pull the REG fuse and then see if the BATT fuse still blows. I don't have a DETAILED schematic of the inside of the MPEM so it's still a process of elimination. If pulling the REG fuse gets everything back up, then the problem seems to be in the rectifier circuit or possibly in the MPEM itself but I can't say that with 100% certainty b/c according to the diagram the current has nowhere else to go but through smaller fuses.

So my diagnosis based on what I see is the problem is most likely in the rectifier circuit, could be a damaged stator or a shorted rectifier. The only way to know is to either unplug the rectifier or yank the REG fuse, if either of these choices eliminates the symptom of the BATT fuse blowing then I'd pursue diagnostic measurements in the rectifier circuit.

In order to conserve 25A fuses(maybe your stock is becoming depleted by now), you should be able to go with a smaller fuse for testing purposes, 15 or 20A, preferably the 20A size.

So, pull the rectifier connector(preferable, IMO) or rectifier fuse out of the circuit and give it another try, hopefully the short goes away and you can concentrate on the charging circuit and eliminate the MPEM itself as a potential cause.

Thank you very much for your help, I will try this and respond back with the results.

 

[watwood1]

Helps narrow it down, yes. I'm looking at the schematic here and see the BATT fuse feeds 5 other fuses, only one of which is the same size, the REG fuse is 25A, so I'd say pull the REG fuse and then see if the BATT fuse still blows. I don't have a DETAILED schematic of the inside of the MPEM so it's still a process of elimination. If pulling the REG fuse gets everything back up, then the problem seems to be in the rectifier circuit or possibly in the MPEM itself but I can't say that with 100% certainty b/c according to the diagram the current has nowhere else to go but through smaller fuses.

So my diagnosis based on what I see is the problem is most likely in the rectifier circuit, could be a damaged stator or a shorted rectifier. The only way to know is to either unplug the rectifier or yank the REG fuse, if either of these choices eliminates the symptom of the BATT fuse blowing then I'd pursue diagnostic measurements in the rectifier circuit.

In order to conserve 25A fuses(maybe your stock is becoming depleted by now), you should be able to go with a smaller fuse for testing purposes, 15 or 20A, preferably the 20A size.

So, pull the rectifier connector(preferable, IMO) or rectifier fuse out of the circuit and give it another try, hopefully the short goes away and you can concentrate on the charging circuit and eliminate the MPEM itself as a potential cause.

We pulled the rectifier connector and still had the same issue,so we decided to go with another MPEM and that fixed it. Thanks for all your help with this.

My last question is does anyone know of a company or a person that might repair MPEMs?