Fried V3 MJLJ ?

Patriq · Post by **Patriq** » Fri Jun 12, 2009 10:11 pm

Hm... don't know if I've managed to fry my V3 MJLJ, or what.

I connected +12V and ground to the pins on the molex. I used a "crocodile's teeth" on both - and they are too big to fit together on the board side, and the jaws are too big to enter where the connector normally goes in. I therefore opened the mouth of one of the jaws to let one half of the jaw enter at the +12V. The other half of the jaw might have clamped on the topside and/or the underside of the pcb. Ground rested nicely on it's pin.
(see photo)

I don't know if that might have shorted it somehow. But MJLJ won't communicate with the COM Port. It was running nicely about a year ago. I haven't ran it since, and got it up from the car just now. I can confirm +12V over the pins, and +5V at the Vref pin and where there are supposed to be +5V at the MAP sensor.

Can I somehow have shorted anything by what I did? Ground is on the surface in general on the underside of the pcb, isn't it ?
In the photo - the yellow wire (or the mouth) was rotated 90 degrees at one point so the one of the jaws touched the pcb whilst I clamped it (to what I thought was the underside of the Molex)

Other than that, I have been playing with the settings for the USB com port with differen baud rates etc. I couldn't find any documentation for either the V3 or the V4 for what the settings should be for the comport (flow, data bits, baudrate etc.) Isn't that documented somewhere ?

Post by **brentp** » Fri Jun 12, 2009 10:23 pm

Patriq,

The config software itself sets the appropriate serial port- so you don't need to do this yourself. When doing the Hyperterminal debugging tests, you would set hyperterminal to 4800 baud, N81 . See the troubleshooting page in our wiki for steps on doing this.

Aside from PC communications, does your MJLJ actually control ignition advance on your engine? This is another way to verify if the unit is functional.

Patriq · Post by **Patriq** » Sat Jun 13, 2009 5:15 am

Unfortunately the engine is not totally reassembled...
So, can't test it there.

Do you mean to say that regardless of what speed I set the com port to be working at, the config software will be able to communicate with MJLJ ? And it works regardless of what flow control it is set to !?

Post by **brentp** » Sat Jun 13, 2009 6:40 am

That is correct. The software sets the necessary serial port parameters when the application start up.

Patriq · Post by **Patriq** » Sat Jun 13, 2009 2:06 pm

brentp wrote:That is correct. The software sets the necessary serial port parameters when the application start up.

Wow, that's neat !

Well, I tried changing to configurator 3.2.1 instead of 3.3.1 that I was running. It struck me that maybe I had an older version of the firmware running. I don't know if that made the difference. I tried a new powersource as well. Anyhow, it worked. I downloaded the table that was on MLJL. Then updated to latest firmware and changed configurator to v.3.3.1. MJLJ now communicates nicely with the configurator !

I'll now try to read values for the temperature sensor over the aux port and see how that goes !