Megajolt Meltdown
Turbo Mini Forums

I had a few problems with my megajolt at the start of the year. I managed to get it sorted by swapping the edis and havent really thought about it since.

At the time I was playing about with trying to get my hardcut add on to work but I didnt have any luck. I have recently tried to get this working but still had no luck. I took my megajolt to bits and found a chip had melted. i must add that the hardcut had been working in the past.



What I cant understand is why the unit still works and has been since the start of the year! I have looked on the autosport labs site and emailed them to see if they sell spares but had no reply.

With my limited knowledge of electronics would this part be unique to the megajolt or something you could buy off the shelf?

From what i have read it is ULN2003 transistor. Does anybody have any ideas?

Cheers Ron

what version, 4?

the uln2000 should be sourceable from rs, maplin etc,

it looks like your chip has go hot at on end, i'm wondering if th 5 v reg has gone squiffy and is chucking high voltage into the uln.

failing that maybe somthing has shorted out, outsid ethe unit.

Edited by Joe C on 14th Sep, 2009.

I forgot to say its a version 3. It was built by Martin MIllener and says fimware v3.21 on the back.

http://uk.rs-online.com/web/search/searchB...N2003AN&x=0&y=0

http://search.digikey.com/scripts/DkSearch...e=497-2344-5-ND

Its an output driver chip for relays and such. They dont like dead shorts or high current, and that looks like whats happened

Probably still works as it looks like its only channel 6 and or 7 thats failed

Edited by Sprocket on 14th Sep, 2009.

Edited by Sprocket on 14th Sep, 2009.

Read the edit ^

I think it melted when i had my original problem. The wiring looked like a snakes wedding. But as you say I will check all the wiring out before I fit the new chip.

I noticed the recess when looking at the build guide I will have a look when the new parts arrive. Thanks again Ron

wow not seen that before!

AlexF

from autosport.. looks like thats why the chip is on a socket.

Usage

The four user-defined outputs provided by the MJLJ can be set to trigger on RPM, Load, or Auxiliary Input thresholds. The separate 'shift light' output triggers only on RPM, but otherwise behaves identically to the user outputs.

The controller firmware applies Hysteresis to the user outputs. For RPM, the hysteresis threshold is 100 RPMs; for Load, the threshold is 1 KPa/1% TPS, and for Auxiliary input, the threshold is 1 configured unit.

The configuration of these outputs is handled bt the Configuration Software- see the Operation Guide for details.

Each output can supply up to 500mA, which is enough to drive LEDs, small incandescent lamps, relays, and small solenoid valves. If you are unsure on the amount of current drawn by the accessory, you can power it manually and measure it's current using a amp meter.

Accessories that have a higher current demand can be controlled by relays, with the MJLJ output driving the relay.

Should you exceed the current capacity of one or more of the user defined outputs and damage the IC that drives the user outputs (ULN2003 darlington array), replace the chip with a new unit- it is socketed for this specific reason.

I run a supercharger and I don't care the TB is on the wrong side.
VEMS + 12 PSI + Liquid Intercooler = Small Bore FUN!

Cheers for the help guys. I have had a word with a mate of mine that sells adaptronic ecus and he says that its a common fault on them when people wire them wrong so he will be sending the chip over! I can pick the holder up from maplin so should be sorted in no time!

Out of interest would this be the same?

http://www.maplin.co.uk/module.aspx?moduleno=2395

yep

Edited by Sprocket on 15th Sep, 2009.