SDL Air Temp reading to low.

[supercharged88]

I have an Autronic SMC connected to a SDL.
Everything works fine except for the engines Air Temp is reading way to low.
The air temp shows correct in the Autronic software as live data.
However the air temp displayed on the SDL or viewed in i2 is alot cooler.
EG yesterday the customer ran the boat to 118 MPH, in the data log downloaded from the ECU the air temp was around 36 to 38 degrees and peaked at 42 degrees celcius at 14 psi, the majority of the log the air temp is around the 34 degrees mark.
However the air temp in i2 peaks at only 4 or 5 degrees celcius.
Engine idling on the hose yesterday, the air temp was 30 degrees and the dash showed 2.4 degrees celcius.
The engine air temp data is sent to the SDL via RS 232 from the SMC.
We ran this same SDL with the old boat that had an Autronic SM4 and never had any issues with the air temp readings.
Any ideas, anybody.
Thanks
Dave.

[supercharged88]

I forgot to mention in Motec Dah Manager Software i am using the SM2-3AT RS232 Template.

[supercharged88]

This afternoon i changed the RS232 template from SM2-3 AT to SM2-3.
The air temp finally read correctly.
However now the TPS value stays at 99% all of the time.

[JamieA]

It sounds as though the template is not matching.

I know that the template changed during a firmware update in SM4 ECU's, but I dont really know too much.

what SMC version are you using?

[supercharged88]

Hi Jamie,
the ECU is a SMC and the firmware chip version is 1.94.
I can confirm that the SM4 template works 100% spot on from using this same SDL and a SM4 with chip version 1.09(which is the latest chip version for an SM4) in the previous race boat.
I have spoken to a friend who has used the SDL with SMC and all worked fine, however he has never used one with a 1.94 chipset.
He has used earlier versions such as a 1.18, i think from memory.
It would appear that the SMC 1.94 may possibly have a different data string or something of that nature.
Swapping the template from RS232 SM2-3AT to SM2-3 and seeing the ACT be corrected but the TPS reading 99% all of the time, tends to indicate to me that there must obviously be some type of difference.
I will see what i can find out in regards to the data string from a 1.94 to earlier versions.
Regards
Dave

[supercharged88]

Hi Jamie,
Autronic has 4 different data streams, from what i can gather,
SMC
SM2-3
SM4 1.07 and prior
SM4 1.09
Obviously when using the SM2-3AT or SM2-3 template when using an SMC ecu will create some sort of data mismatch,
EG; my problem.
If i can supply you with the SMC data stream info,
Would your software engineers be willing to create a dash template for the SMC.
Thanks
Regards
Dave.

[supercharged88]

Hi,
here is the Data Steam protocol for Autronic SMC 1.91 onwards.

[supercharged88]

Hi Simon,
is there any chance of a template for the SMC being created.
Regards
Dave.