Skip to main content
Topic: A diagnostic problem -- where would you start? (Read 707 times) previous topic - next topic
0 Members and 1 Guest are viewing this topic.

A diagnostic problem -- where would you start?

Yahoo Message Number: 116062
OK folks -- here's a problem to solve. If you have had any of the same experiences, I would love to hear from you. We were on our way from Reno, NV to Bozeman, MT. yesterday afternoon when our 2003 CC Magna crapped out in the middle of the Nevada desert. I managed to nurse it home, stopping frequently to let it rest, and finally made it, to our great relief. To those of you who would like to hazard a guess as to what led to the problem, here are the symptoms. As I said, I would greatly appreciate any advice.

Thanks in advance,
David Jarrett
2003 CC Magna #6240

center
center
center
CONDITIONS:

1)    Transmission goes into limp mode after a few minutes of driving. After stopping, turning off ignition and waiting a few minutes, resumes normal function for a few minutes before going into mode again.  Once in this mode, it will not shift, but will stay in gear selected when restarted, and will respond to throttle control.
2)    Transmission keypad goes completely black, with no codes showing, but "check transmission" light is on. When prompted for codes:
A)    With engine running, keypad window counts down from 7 to 1 and then announces oL OK.
B)    With engine off, keypad window shows oL 5.0 (Engine speed too low).
3)    On Silverleaf display, most functions (including RPMs, temps, battery voltage @13.8V, HP %, etc.) displayed accurately with the following exceptions:
A)    Speed shows 0.
B)    Cruise control setting shows 0 even though cruise control is set and working.
C)    Instant MPG shows 0.
4)    Dash gauges:
A)    Voltmeter shows 13.5V+ except when ignition turned off, when it drops to 0 (this it has never done before).
B)    Speedometer and odometer function erratically at first and then stop working altogether.
C)    Jake brake light comes on along with the above, even though it is not activated.