1985-1998 [Subscribe to Daily Digest] |
![]() | [Main 9000 Bulletin Board | BBFAQ |
Prev by Date | Next by Date | Post Followup ]
Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
Trionic OBD-II port autistic--am I doing something.... Posted by TonyJ [Email] ![]() ![]() ![]() |
wrong? Our 97 is getting 24-27 MPG; a couple MPG less than we have come to expect. It runs smoothly and boosts well into the red. There are no fault indicators on. I just replaced the plugs with new NGKs and am running some Techron through it. I also checked the front O2 sensor ground, which had been a problem in our Aero. (They added a separate ground wire to the newer cars, as well as a second sensor post-CAT.)
So I thought I would look at what's going on via my OBD-scan, which connects to a Palm Pilot. But it never establishes RS-232 communications. The OBD-scan is OK; I verified that by connecting it to my 2002 RSX-S. I determined pin connections from my Saab shop manual, which I have recently extended to cover through '98. There is "+30" (always there) power and 2 ground pins. My main concern is Pin 7, which goes to the Trionic ECU (It also works for ISAT). There are a few other pins for other computers (SRS, TCS, EDU, Driver's seat, etc.) and another pin goes to the fuel pump relay coil where it connects to the ECU. Everything looked fine to my DVM, except that pin 7 has 6.55 VDC on it and I can measure no AC, so there must be no waveform. The voltage appears regulated; i.e. it meaures the same with the engine runnung or off as the supply varies between 14.1 and 12.5 volts. I haven't hooked up my o'scope yet.
Is there any Trick to getting it started? I tried driving it ~10 miles, but it acts the same.
Is my Trionic ECU toast or just autistic? The wire couldn't be shorted to ground or open, or I wouldn't see a solid voltage at the OBD connector.
What else could be knocking down the mileage? Thanks in advance for any advice.
TonyJ
94 Aero 5 sp. 94K
97 CSE turbo 5 sp. 90K
posted by 24.34.16...
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
![]() |
![]() |
![]() |
![]() |
![]() |