There's no polarity . . .
to a CH; you can't install them incorrectly.
But you could have a bad wiring harness; they do go bad. Just remove the CH and reset the codes. Wait a short time and re-read them.
Also use an ohmeter to tell if the B10/8 sensor is REALLY open; it should read around 350 ohms or so at 90C apx. If it reads open, or much higher than that, then r&r.
Regards . . . . JimF
'94 S500 Cpe
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