Originally Posted by edgecase (Post 2691817)

I am in the process of repairing a Bombardier MPEM for a 2002 Traxter for a local bike shop. I do various kinds of electrical and electronic repairs for this customer, and they contacted me when the repair shop reached a dead-end on the electrical problem, and the cost of a new MPEM was prohibitive.

If you still have the old MPEM, and you can confirm the same symptoms, I may be able to repair the module economically. Send me a private message if you are interested.

The blowing fuse problem is caused by a shorted diode. The customer was "boosting" the Traxter due do a bad battery. It started and ran a short time with the lights flickering (due to the short). The next attempt to start it failed. If the fuse is replaced with the standard size, it blows when the ignition switch (key) is turned on. If the fuse is replaced with a 30 amp (careful here... this was done with an external battery and jumper cables, which likely limit the possibility of dammage due to over current) there is a faint ticking sound. This is the result of an oscillation caused by the key turning on a transistor, switching on power to the circuit with the shorted diode. The short caused the voltage to drop, switching off the transistor, removing the short, which causes the voltage to rise again, and the cycle repeats.

If you have a Traxter, I suggest you don't *ever* try to start it from another vehicle with the engine running. I believe the shorted diode is a result of "boosting", where the running vehicle's alternator overshoots the voltage at the instant you stop cranking the Traxter, frying the MPEM. Jump starting from a nother battery, possibly in a vehicle, should be OK though.

Originally Posted by jag1963 (Post 3325671)

Hello all,im working on a 500 bombardier traxter and having a hell of a time to figure it out,the timming is completly screwed up cus it backfires through the carb and wont try to start.it belongs to a buddy of mine,and i have the unfortunate job to try to fix it.the more i read up on this i think maybe it could be the mpem.it had been running fairly bad up until a few weeks ago but now it wont start at all,all kind of spark but i think the timming is off,as it just backfires through the carb steady,would much appreciate all the help i can get.

Originally Posted by electromatic (Post 3375553)

I cut the cases open and replace the blown diode or diodes (sometime up to three are blown or shorted. My cost to fix them is $200.
I have fixed about 5 this way
finkelstein@charter.net
Burl 770 251 4080

Originally Posted by electromatic (Post 3407732)

Generally the MPEM works or it does not. If the 20 A fuse does not blow and the lights come on and engine cranks the MPEM is OK.

I have fixed 6 or 7 of the MPEMs for people. The problem happens after a dead battery and jumping the system. One or more of the power conditioning diodes blow and short.
The only MPEMs that I have been able to fix are the ones that are large square ones with two plug sockets on the face.
I cut them open and test the components and replace the bad diodes then report the electronics. I don't use thinners as that damages the capacitors I know just where to cut and test.
I fix them for $200 and don't charge if they don't work
Burl or Jake 770 251 4080