VEMS Community Forum

Technical => Wideband & EGT Gauge => Topic started by: multiplex on September 02, 2010, 01:49:56 PM

Title: EGT not reading correctly after FW upgrade
Post by: multiplex on September 02, 2010, 01:49:56 PM
helping a buddy out with his new round.  When installed, it was running .2 Firmware.  I figured it would be a good idea to get him upgraded to the latest and greatest. I installed 1.4.5

Previous to me doing this, he mentioned the EGT was reading fine - although he never ran the motor, just measured air temp.

after the upgrade, there seems to be no change on the EGT readings. I unplugged the sensor - no change. Shorted the wires - no change.

I then tried to go back to .2 firmware, but VT was crashing.

Any thoughts on what to try?  Should I be using megatune for all of this?

Title: Re: EGT not reading correctly after FW upgrade
Post by: [email protected] on September 02, 2010, 02:00:55 PM
Are the calibration and offset settings still correct?
Title: Re: EGT not reading correctly after FW upgrade
Post by: multiplex on September 02, 2010, 04:59:43 PM
yeah those were maintained during the upgrade.

After the upgrade it was reading 2296 for temp.  I played with the calibration, and eventually had it reading with an 'f' as the last digit.  But no change with the sensor disconnected.

question - is the unit shipped by default with it set to Celsius?

Title: Re: EGT not reading correctly after FW upgrade
Post by: [email protected] on September 02, 2010, 10:12:44 PM
the C or F is set in the tuning program - the ECU uses the raw value.
Title: Re: EGT not reading correctly after FW upgrade
Post by: multiplex on September 02, 2010, 11:23:54 PM
understood.

reason i ask is i'm trying to decipher if the issue existed prior to upgrading the firmware.

i remember using VT to change from C to F or from F to C, but couldn't remember what it was set to first.  I was the first person to 'log' into the device since new

the person i'm trying to help says the temp was reading correctly, being around 94F.  just wondering if by default it was in C, there for the numbers wouldn't make sense.

after the upgrade it also read 94, but did not increase once the motor was started

its possible there was some improper voltages attached to the EGT wires while he was wiring it up.  I'm trying to figure out if that might have done some damage or not

Title: Re: EGT not reading correctly after FW upgrade
Post by: [email protected] on September 03, 2010, 08:46:22 AM
Well normally without an egt sensor connected the thing reads its 1250C max, then when you bridge the wires then you get something similar to atmospheric temperature.
It does sound as if something unpleasant has happened to the thermocouple conditioning chip.
Title: Re: EGT not reading correctly after FW upgrade
Post by: multiplex on September 17, 2010, 01:21:13 PM
are the schematics for the round published anywhere?  Can anyone comfirm that the same chip EGT from v3 is used in the round?

Looks like i need to replace that on this unit, and go from there.

Title: Re: EGT not reading correctly after FW upgrade
Post by: [email protected] on September 17, 2010, 04:30:31 PM
You cannot repair the round I'm afraid.
Title: Re: EGT not reading correctly after FW upgrade
Post by: multiplex on September 17, 2010, 07:09:31 PM
oh boy   :'(

i was afraid of that to some degree - it looks enclosed rather tightly.

Title: Re: EGT not reading correctly after FW upgrade
Post by: [email protected] on September 17, 2010, 07:56:02 PM
Mission impossible style it destroys itself when tampered with
Title: Re: EGT not reading correctly after FW upgrade
Post by: DI-Racing on September 17, 2010, 11:25:12 PM
try ab-sailing from the ceiling and sneaking up on it,,worth a try..(sorry, that was a very childish thing to say..i shall return to driftworks,quick sharp...,,;-)