TestPoint
Well-Known Member
- Joined
- August 21, 2009
- Messages
- 395
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- City, State
- Ellijay
- Year, Model & Trim Level
- '00 5.0 in an '82 Volvo
I had posted the quote below some time ago and it appears to be true as my transmission shifts exactly as I expect it to. The shift pattern needs to be 'tuned' as the Volvo is a thousand pounds lighter than the Explorer and the rear end ratio is substantially different. At least those two items are still on my unresolved list. The fine details of how to mix and match early/late harnesses and late Digital Transmission Range Sensors (DTR) with early/late PCM's stills seems to be outstanding. I escaped the above by having harness/DTR/PCM of the same era.
I suspect that the DTR, which is the external switch unit on the shift shaft, could be added to the '96-'97 transmissions and with appropriate harness modification will work just fine with the later PCM.
The transmissions did not change internally during this series.
Anyone solving merging all this please post to this thread what works and what doesn't.
I suspect that the DTR, which is the external switch unit on the shift shaft, could be added to the '96-'97 transmissions and with appropriate harness modification will work just fine with the later PCM.
The transmissions did not change internally during this series.
Anyone solving merging all this please post to this thread what works and what doesn't.
Earlier posts left the transmission control issue hanging regarding whether the Variable Speed Sensor (VSS) or the (Transmission) Output Shaft Sensor (OSS) provided input to the PCM for shift management.
I just found a note on page 30-3 of the Wiring Diagrams associated with the OSS that reads:
"The frequency from this sensor supplies the PCM with output shaft speed information. This information is used in determining shift scheduling, torque converter engagement schedules and EPC pressure."
That is in reference to the 2WD vehicles. The Variable Speed Sensor (VSS), located on the rear axle, is input for the PCM apparently only on the 4WD vehicles.