1996 Speedster difficulty starting and cuts off

[clarke]

My 1996 Speedster will start one minute and will not start the next. If one engine starts the other one will start, if one engine wont start, the other engine wont start. Sometimes I get beeps and other times i do not. Both Tachohmeters are stuck on 5000. Once i get it started and underway, both engines will cut off at the same time like the key was pulled of the post. here are some things i have done:
1. installed new DESS post - no luck
2. purchased and programmed a new key - no luck
3. ran new wires from DESS post to MPEM box - no luck
4. checked fuses in the MPEM box - all are fine
5. checked the throttle position switch - loose wire, resoldered, still no luck

Please help!

 

[clarke]

advance diagnostic

I went thru the advanced diagnostic mode and got two short beeps after attaching the lanyard and pressing start buttons. What does this mean?

 

[timmyboy76]

Clarke...check the battery/ground cables.

 

[seadoosnipe]

Advanced diagnostics....

Two beeps in advanced diagnostics means the MPEM can't read your ROM chip in your lanyard cap. Two beeps also means your engine is ready to start, depending on whether your in basic or advanced. So, when you stated the two beeps in advanced diagnostics, did you hear the one short, one long beep when you pushed the start/stop button 5 times?

Where did you get your post. This issue sounds exactly like it is your DESS post. For the age of the boat, it's about time to replace it anyway. But, if you got it from someplace like ebay, ...........get a new one. One from an OEM distributer.

The other thing that is weird, if you got new lanyards and was able to program them, how did he do it if the MPEM wasnt' picking up a reading from the DESS post?..............:cheers:

 

[clarke]

I checked the battery/ground cables, feel tight and look ok.

I get the two beeps in advance mode, but the key will start the engines sometime and most time it will not start the engines.

I put a brand new DESS post in last summer. It came from a seadoo dealer. I checked the DESS post last night for continuity using the following method:
using a test probe, no key, black wire to black-yellow wire got no continuity; white-grey wire to post terminal 0 ohm; black wire to post ring 0 ohm;
key on, black wire to black-yellow wire 0 ohm.

Also, the timer seems to be working ok, press start button with no key, lights come on for about 33 seconds.

When i bought the new key on Monday from a seadoo dealer, He had trouble programming the key. He kept getting "BAD CONNECTION" message on his handheld programer. He kept trying and trying and he finaaly got the key programmed and the boat sarted with the key.

With the key on and press start button, I can hear a click noise comming from the grey box, but nothing else. After puting the key on and off the post several times, the engines will start, then they wont!

 

[clarke]

I have been reading other threads with similiar problem. One guy fixed the problem on a challeger by removing the magneto cover and replacing the pickup that he said was broken and just hanging. Could this be my problem, what are the odds that both of my engines have the same problem?

 

[glenwhitt]

Pickup broke guy was me. Not your problem. Mine was turning over every time, just no spark. Pickup will cause your problem. If you are getting a click noise from the grey box but starter not turning over then the lanyard and post are working. It is either a wire/cable or ground connection or maybe a bad solenoid.

You have two grey boxes? Do you have two batteries? Look for something that is common for both motors since they both start/not start at the same times. Like a single bad ground cable. The odds of haveing two seperate parts on each system failing at the same times like this are pretty out there

 

[clarke]

I have one grey box, one DESS post, one key and one MPEM. I have two batterries and two of everything else.

I checked the battery cables and the ground. All seemed to be ok. I checked the batery voltage by touching the pos. battery post with one probe and the both engine blocks with the other and got 12.32 volts which leads me to believe the ground wires are ok.

I am starting to fear that the MPEM is not working properly. The five amp fuse is fine as well as the other fuses. The fuses have never blown.

Can the MPEM be bad and not blow fuses? Does the MPEM either work or it doesn't?

I sure hope that it is a simple wire problem! I have looked at the wires and they look ok.S

Sometime the engines start and most times they dont. When they do, they will cut off like the key was pulled off the post.

Thanks for the help.

 

[clarke]

ok, I just jumped the solenoids and both engines turned over.

Wires from DESS post back to the wire harness at the electrical box are good.

Still starts sometimes and doesnt start sometimes.

Would a short or bad connection in the bilge pump wires cause a problem like i am experiencing?

 

[glenwhitt]

a few post up you say that with lanyard on and you press start button you get a click noise in the grey box. Do you get this all the time when trying to start and engines do not turn over? When engine does turn over does it start?

Depending on the answers above you will want to get the wiring digram and start tracing the path.

 

[kustomkarl]

I got a feeling that the problem is in the ground- or the positive+ wires between the batteries and the engine. If the ends just look ok it still might be corroded on the inside and not making a good connection. I suggest cutting off the ends and install new ends on the both cables and clean the area where they connect on the engine for ground and in the mpem box. I have seen this exact problem lots of times before. If you don't get a good connection(+-) even the post reprograming will be a problem, like it was.

Karl