Map corruption

Discuss issues and tuning software like DTASWin, E-Race, MegaLogViewer(DTA), etc. Also post archive versions of firmware.
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David Ferguson
Posts: 18
Joined: Sun Jan 23, 2022 6:37 pm
ECU Model: S60 Pro
Firmware Version: 78.01
Location: Paso Robles, California

Map corruption

Post by David Ferguson »

A Norma M20FC with a Honda K20, and DTAfast S60 ECU V78.01 (and SXWheel) has found it's way to my shop. Was able to connect to the Cosworth GCU, and at least try to communicate with the DTAfast ECU I was unable to stay connected using Windows 7 or WIndows 10 laptops and my favorite USB Serial Adapter (The Keyspan/Triplite HS-19).

Reading the help documentation in DTAswin 90.30, I noted that the prolific chipset was preferred, so I bought a couple of adapters and they seem to be working (latest Prolific driver 3.8.41.0) However I did notice some Map corruption (for example sensors scaling maps for Water Temp would just have a bad voltage value in the middle of a table, or some of the temps would have zeros.

The problem the car was brought in for (not displaying gear properly) was one of these where there was a bad voltage for gear 5, in the Gear Position Map.

Anyway, fixed various maps, and used F4 to update maps on the ECU. Things seemed to be working. But moved the car onto the dyno, and after a couple of coughs during the first attempt at starting -- nothing for the next 3 days. I noticed voltage reported in the ECU was low (even though engine was turning over at 400 rpm. Checked diagnostics and engine was getting sync. I originally did not have the FIFO setting as described in the help / manual, but I've done that and have not seen any improvement.

I was reviewing settings, and found General Engine Settings now had the Ultimate RPM limit set to 60 RPM. Ah ha, I thought fixed this and still nothing. Finally I decided to just send the first map I retrieved from the ECU (still had the bad gear and bad sensor values). Car fired right up.

OK, no problem, I'll start from there again. I made changes to bad sensor maps. All of the sudden I noticed that only some of the CAN info was making to the SX Wheel display (RPM & Water Temp, no Gear, oil pressure, oil temp, fuel pressure). I went to the Data Stream map, and the Bitrate and extended ID sections were grayed out. Toggling off/On Standard CAN Stream On, and updating with F4 got things working again.

I'm updated the fuel map, and all of the sudden car won't start again -- somehow Flywheel mode changed from 7 - Honda K20 A, or Ford 36-1. Load old map -- fires right up.

So, is there a firmware issue or laptop comms issue? Any suggestions - update firmware? Change baud rate?
What are the best techniques for comparing maps to see what has changed?
Is there anything I can provide that will help someone understand what might be happening?

Thanks in advance for any help you can provide.

David Ferguson
Veracity Racing Data
Paso Robles, California
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