On Sat, 18 Dec 2010 20:26:25 +0000 Oli Glaser wrote: > I think he means the lower 4 bits of the ADCON1 register for the 0010. > I took the 0x3b00 to mean ADRESH =3D 0x3b, ADRESL =3D 0x00 =3D 236 decima= l (if=20 > left justified, which looks to be the default) > Little more info about the rest of the registers and stuff like which=20 > pin is being used would be useful though. Sorry about the noise... I found the problem: Everything was correct (well, almost). The only problem was that (in my program) the sample setup wait was only active when selecting A/D channel 0. It didn't operate on the other channels, so, when reading channel 2, I got strange values. Incredibly stable, but wrong values. Even large temperature variations - 20C outside to 80C+ under the hood - didn't change the sample setup time constant, it seems. Any, thanks for all the suggestions... Now I just have to find out why the car is overheating... But that's for another list, I guess. John --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .