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97 SPX bad MPEM or bad DESS key/lanyard?

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97SPX

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Newbee here, just bought a 97 spx. It has what I think is a bad key but I hope is not a bad MPEM. Here are the facts so far.

New charged battery.
All fuses good.
Ran last year.
put lanyard on = no beeps at all.
no lanyard, press start = guages come up, trim works no crank.
no lanyard, press start X5 = one short one long (advanced diagnostic mode).
put lanyard back on, no beeps at all.
post has continuity from ring and center post all the way to MPEM inside grey box

no matter what combination I use I get no difference with lanyard off or on. Points to bad key.
should lanyard terminals show continuity center to outside or some Ohm value?

Unless someone has another test to try I will probably take it to the dealer and have them check the key. I'm trying to avoid the dealership at all costs as I am on the mother of all budgets. Any suggestions on further diagnostics would be appreciated. I have a meter and am reasonably mechanically inclined.

Thanks, great forum by the way.
 
Welcome to the seadoo forum 97 spx. I would start by cleaning the Post on the safety lanyard. It is beeping and saying it isn't connecting to the Mpem, (Multi Purpose Electronic Module) It needs to beep 2 times to let you know it is ready to start. Clean the post and cap with soapy water. Don't use any grease of lubricant on it as it needs a clean connection to make contact. Connect the lanyard to see if it is making a connection. 2 beeps and it's ready to fire up.
Here are some advanced test for you.Engine start/stop switch verification;
Disconnect the Yellow/Red wire of the start/stop switch. Using an ohmmeter, connect test probes to the Yellow/Red wire and to ground. Measure resistance, it must be an open circuit (switch is normally open). Depress and hold switch, the ohmmeter should read close to “0” ohm.

Safety Lanyard Switch Verification;
If 2 short beeps are not heard when installing the safety lanyard, disconnect the switch wires.
Safety lanyard removed;
connect the test probes to switch Black and Black/Yellow wires. It’s an open circuit, there should be no continuity.
Connect one test probe to the White/Gray wire and the other test probe to the switch terminal. Measure resistance, it should be “0” ohm. Connect one test probe to the Black wire and the other test probe to the switch ring. Measure resistance, it must be close to “0” ohm.
Safety lanyard on switch; connect the probes to switch Black and Black /Yellow wires. Measure resistance, it must be “0” ohm.
Timer Verification;
The timer is integrated into the MPEM. Always confirm that the fuses are in good condition. To confirm operation of timer, remove the safety lanyard from switch. After 5 seconds delay, depress start/stop button once. The timer should stay on for 33 seconds (for example, the gauge(s) will be activated) and than turn off.

I hope this helps.

Karl
 
if it was a wrong key, it would give one long beep. the fact that it doesn't beep at all makes me think it isn't seeing the key at all. do you have a friend with a DESS seadoo? try his key. one long beep is what you should hear. if so, you most likely need a new key, which means dealer has to program it.
 
Thanks guys for the quick responses.

Karl, I'll try your test procedure as soon as i can find time and I'll be sure to post my results.

Derek, I thought of that so I'm taking my lanyard to my local dealer to see if they will let me try it on one of their ski's at the shop to see if I get the long tone or if doesn't see it at all.

If I meter the key itself should I see continuity from the center post to the ring or should i get an Ohm reading?

Thanks again for all the help.
 
You'll get ohm's resistance from the ROM chip in the lanyard, and magnet to keep it attached
 
Update

Well I charged the bettery and put the whole thing back together. Today I took it to the local Seadoo dealer to see if he could reprogram my key or program another. My wallet and I prepared for the worst. When we got out there I said "let me show you what it's doing. when you put my key on it you should hear two beeps and you don't hear anything"......about that time it gave two cheerful beeps for the first time and turned right over!!! So for the moment this problem seems to have miraculously healed itself. This weekend I'll check everything else and actually start it on the hose. I may even put it in the water for the first time on Sunday and see if it floats!!!

Thanks to all for the help and advice.
 
Just got home from work and actually tried to start the motor, it started on about the third try and sounds solid. The first water test will probably be Sunday afternoon.
 
Karl,

Ran it yesterday for about 45 minutes. It seems louder than I expected. I think it may be because the gasket on the front basket is gone so it may have been vibrating against the body. Next up is my oil dilema. See my other post for that.

Thanks for all your help.
 
dess post is dirty. a little stuff or corrosion and it won't see the right key, the wrong key, or even key biscayne.
 
Never did find the root cause, just a miracle cure. It hasn't given me a lick of trouble since. I would guess dirty post but who knows.
 
Magnetic's.....

The DESS post is a magnetic communicator between the ROM (read only memory) lanyard cap and the MPEM. Over time, this post loses it's ability to maintain that magnetic contact.

You may be cruising and it just go dead. Put it back in neutral, sometimes, just pull the lanyard and put it back on, then it fires right up.

If you continue to have this problem, it's the DESS post, about to go out on you. You'll need to replace this post. There is no special tools or a need to take it to a shop. Just by the post and install it.

I know, I had this problem 2 seasons ago, I replaced my post and haven't had a shutdown since.................:cheers:
 
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