Volvo 740 orginal CLT & IAT

m · Post by m » Fri Jul 06, 2007 1:56 am

Where kan I find the ohm values for these sensors?Or can I use them direct with my MS without a pullup resistor?
Thanks

renns · Post by **renns** » Fri Jul 06, 2007 3:48 am

Check the factory service manual for your vehicle. The bias resistor for these voltage divider circuits is built in to the MS. You may need to change bias resistor value if your thermistors resistances differ significantly from the GM defaults.

Roger.

m · Post by m » Fri Jul 06, 2007 4:03 am

Ok, but can i use Easytherm instead of changing anything in the board (bias resistors i mean)?

renns · Post by **renns** » Fri Jul 06, 2007 8:32 am

Easytherm can compensate for any thermistor's values, but if your sensor's characteristics are way off the GM standard, then the measurement resolution may be poor (say 5 degrees per increment). That is a limitation of the 8-bit analog to digital conversion that is included in the MS1 processor. To correct for this, the bias resistor is changed out to one that is roughly equal to the sensors resistance at room temp. Then the resolution will be back down to 1 degree or so throughout most of the operating range.

Roger.

m · Post by m » Sat Jul 07, 2007 2:18 am

Thank you Roger a last question and i am done.
Can I use the defaults on Boch sensor pÃƒÂ¥ Easytherm with my Boch sensor
0 280 130 026 ? How should i copy or where the inc file in megatune?

Thanks
m

renns · Post by **renns** » Sat Jul 07, 2007 4:21 am

m,

Try the Bosch defaults, and see how they work out. I have no idea if all Bosch sensors are the same in that regard. When complete, copy the .inc files to the car1/mtCfg folder. What I do is copy the original .s19 to the car1 folder prior to running EasyTherm. Then the transfer of .inc files to the mtCfg folder will be automatic.

Roger.

m · Post by m » Sat Jul 07, 2007 6:38 am

Ok
I have asked this question in another link but sorry I am a little bit bak :oops:
I use MT extra 029V and when i create a new .19S files by ET i can flash it in my MS box, but do i have to copy the " s19 mod" in the MT in car1 or it gets there atomatic.?
Thank you for your pasient :D

renns · Post by **renns** » Sat Jul 07, 2007 7:34 am

MT doesn't care about the .s19 file. The .s19 file is only for flashing to the processor in the MS box. If the flashing step was successful, you no longer need that .s19.

Roger.