98 GSX Limited Mpem ????

[Gmetz]

I'm having a cranking problem with a 98 GSX and wanted to know if anyone has any knowledge of the internals of the mpem. The engine spins over fine if you jump the starter solenoid but it wont with the start switch. I ohmed out the start switch to the mpem and its good. I also ohmed out from the mpem to the starter solenoid and its good. I also put a 12 volt jumper to the starter solenoid positive and it cranks over just fine.
So I have eliminated any issue from the solenoid to the starter. The problem is the signal coming out of the mpem to the solenoid and hence my question.

Is the mpem all solid state or am I dealing with a small relay in there for the start solenoid power?
Also, can the dess post cause any cranking issue other than just not cranking at all?
Forgot to mention that you can hit the start button and about 1 in 10 it will spin over normal.

Thanks for any input......just want to prove that its in the mpem before dropping $400 on a used one.

 

[jhjesse]

I'm having a cranking problem with a 98 GSX and wanted to know if anyone has any knowledge of the internals of the mpem. The engine spins over fine if you jump the starter solenoid but it wont with the start switch. I ohmed out the start switch to the mpem and its good. I also ohmed out from the mpem to the starter solenoid and its good. I also put a 12 volt jumper to the starter solenoid positive and it cranks over just fine.
So I have eliminated any issue from the solenoid to the starter. The problem is the signal coming out of the mpem to the solenoid and hence my question.

Is the mpem all solid state or am I dealing with a small relay in there for the start solenoid power?
Also, can the dess post cause any cranking issue other than just not cranking at all?
Forgot to mention that you can hit the start button and about 1 in 10 it will spin over normal.

Thanks for any input......just want to prove that its in the mpem before dropping $400 on a used one.

Inside the MPEM are some fuses make sure they are all good.
Inside the rear electrical box below the solenoid is a 15 amp fuse. Make sure it is good.
If all fuses are good then replace the DESS post.

 

[Gmetz]

Thanks Jesse! All the fuses are in good shape.

I did notice that the dess is very sensitive and has to be perfect for it to crank.
Do I have to get the dess lanyard reprogrammed if I install a new post? Thanks for the help,
Greg

 

[Minnetonka4me]

They are just real fussy...as long as it isnt cutting out you should be fine.

 

[seadooya]

if you jumped the relay, and motor kicked over, but wont when starter button depressed, then it sounds like a relay/starter solenoid to me?

 

[Gmetz]

Seadooya.......I mentioned that I also jumped 12v into the starter solenoid and it spins over just fine. That proves the solenoid is good. Its losing the voltage out of the mpem or the signal in thru the dess post. I have checked out all the wiring and its in good shape and has good continuity.

The start stop switch is just a loop circuit to trigger the mpem best I can figure from wiring diagrams. I guess they wired it to the mpem so it can function as a start and stop depending on engine running or not.

As stated above, I guess I will try replacing the dess post as its the least expensive at this point!

 

[seadooya]

if you jumped it on the post, that the cable, from relay to starter, is, then yes, it'll turn the motor over/kick out the starter. Theres no "block" at that point.

Pull the relay outta the 94 seadoo, and try it.

 

[Gmetz]

Ooops! Seadooya, mean't to say starter relay....the one in the back electrical box. Thats the one i jumped in 12v power to and its fine. That wire all the way up to the mpem.

 

[seadooya]

if you jumped it on the post, that the cable, from relay to starter, is, then yes, it'll turn the motor over/kick out the starter. Theres no "block" at that point.

Pull the relay outta the 94 seadoo, and try it.

....................

 

[Gmetz]

Sorry! Let me start over!

First, I jumped the starter relay and it spins over fine, but that doesn't say the solenoid is good.

Second, I put a jumper wire to the small pin "yellow" wire on the starter relay plug and it pulls the relay and spins over just fine.

My conclusion is I'm good from the starter relay down to the starter!

 

[jhjesse]

Thanks Jesse! All the fuses are in good shape.

I did notice that the dess is very sensitive and has to be perfect for it to crank.
Do I have to get the dess lanyard reprogrammed if I install a new post? Thanks for the help,
Greg

No, only if you replace the MPEM

 

[jhjesse]

Forgot to mention that you can hit the start button and about 1 in 10 it will spin over normal.

Thanks for any input......just want to prove that its in the mpem before dropping $400 on a used one.

Seadooya in post #1 Gmetz stated that one in ten times it will spin over with the start/stop switch.

I, just like you, thought starter relay/solenoid at first until I re read the last sentence.

How is sunny CA? Was looking at youtube yesterday and watching a challenger do some wave jumping off the shore of Long Beach.