LS1LT1 Forum banner

Datamaster dtc data question

1405 Views 7 Replies 2 Participants Last post by  bobdec
Datalogging my car yesterday and notice I have a dtc 21 tps high set under transmission data but does not have any codes set in the engine data. Is this normal. I know some codes only read in trans data or vice versa. But it shows green under engine data as if it monitors that code but has not set a fault.
1 - 8 of 8 Posts
Did you synchronize both engine and transmission log windows to each other. There is a selection box on the transmission display window labeled " Sync' . It's just to the right of the record number scroll bar. Click that box and it will sync the transmission data log window to the engine data log window. The DTC 21 displaying in the tranny log s/b the engine DTC, it's displayed there because the DTC 21 will put the tranny into safe mode.
After clicking sync, the time of day box above the record number s/b within a second and the log time XXX.XXX s/b within thousandths of a second of the engine window.
If DTC 21 does not display on engine log window after syncing the logs, then I'm at a loss. Would have to be something fluky w/Datamaster or the PCM scanning out the wrong data or Datamaster analysis of the scanned data.
Ill try to sync it next time. Maybe thats one part of my crazy transmission problems
The DTC 21 will disengage TCC and change your shifting characteristics, hard shifts, and shift points. DTC 21 is caused by TPS voltage above 2.5 volts and airflow below 10 AFGS (at idle and TPS says throttle is depressed) - OR- TPS voltage is greater than 4.8 volts (invalid level). The engine log shows all the conditions (TPS voltage, AFGS) mentioned to verify when DTC occurred.
I dont see a sync window anywheres. Looked under engine, transmission. And under recording new log.

At idle my tps is 0.57 volts, 0% tps, and afgs is between 6.4 to7.4.
At wot 100% tps, voltage hit max of 4.22 volts and drops as low as 3.8volts, afgs 190-244.
Tho the dtc is set as soon as my log begins. Car was only running 30 seconds to a minute before I hit record. Could have had a fault before I had hit record.

Bringing it home from work tomorrow. Ill clear dtc's and see if it resets.
Must be a version difference.. You can manually sync using the time stamps, record numbers will not be equal in most cases. Here's a pic of my screen w/sync box, never updated Datamaster since I installed it back in 04-05, a mess to get re-registered if you loose the program, why mess with a working thing.
See less See more
Maybe mine is newer. Dowloaded it last year sometime. Theres a drop down menue saying engine data, transmission data, or engine and transmission data. When i do both the trans data is in separate window and has its own logs and graphs
Correct , display above is the Transmission log screen.. to sync the two logs together the timestamp and the log timer, two boxes above record number should be close to the same as the engine log display window (not shown).
1 - 8 of 8 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.