So, I had PRNDL set to monitor in the scanner, but I don't have the PRNDL switch installed yet. What I don't get is with PRNDL set to 'none', the PRNDL status shows the gears exactly as you shift . But, if you set PRNDL to PRNDL, then the status shows D4 all the time.
Would love to understand.
Peter
Peter Young
1966 LandCruiser FJ40 with 6.0l Gen 3 vortec and 4L80E.
1984 LandCruiser FJ60 with 5.3l Gen 3 vortec, Magnusen supercharger, and 4L60E
I got an answer to this. On the 4L80E and 4L60E (and the 6Ls as well, I believe) the PCM knows where the gear selector is by the pressure switch. PRNDL is only used for idle and to let the ECM know when it is in D3, 2, or 1 so it can be 'smart' about shift points. Since my rig is a conversion, I don't need any of that. I set PRNDL to 'none' and it all works great. If I set PRNDL to PRNDL, then it acts weird as it always thinks it's in D4.
Peter Young
1966 LandCruiser FJ40 with 6.0l Gen 3 vortec and 4L80E.
1984 LandCruiser FJ60 with 5.3l Gen 3 vortec, Magnusen supercharger, and 4L60E
on a manual car, the ECU guesses what gear it is in based on rpm and MPH. I wonder if that is the same when you set it to NONE.
2010 Camaro LS3 (E38 ECU - Spark only). MS3X running complete RTT fuel control (wideband).
Whipple 2.9L, 3.875" Pulley, kit injectors, supplied MSD Boost-A-Pump, stock pump
LG Motorsports 1 7/8" Headers - No Cats, stock mid pipe with JBA Axle Back
ZL1 Wheels/Tires
No, my understanding is that it is not guessing. Apparently, it can tell by a pressure switch in the transmission what gear it is in. It doesn't have to guess. However, there is a lot less intelligence to, say, being in 2nd. Without PRNDL, being ind 2nd is like the old day, it's in second all the time, won't go into first. Using PRNDL, being in 2nd the car will still shift into 1st and be smart.
Peter Young
1966 LandCruiser FJ40 with 6.0l Gen 3 vortec and 4L80E.
1984 LandCruiser FJ60 with 5.3l Gen 3 vortec, Magnusen supercharger, and 4L60E
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