As suggested by @justme, the MAX3232 is not necessary in this circuit. I connected Pin 23 of MAX3162 to pin 10 on SC18IM700 (DI to TX) and Pin 11 on MAX3162 to Pin 9 on SC18IM700 (RO to RX). I've tied Pin 15 and 24 to VCC as suggested by @brhans.
Thanks for all the help everyone. I really appreciate it.
The small error might just be the that RS485 A/B lines should be -TX and +TX instead of +RX.
But it also contains more severe design errors, such as level-converting the RS232 link back to RS232 levels for the I2C protocol converter chip, instead of using 3.3V levels. It might have damaged the I2C protocol converter.
And the MAX3232 is actually not needed at ...
CAN bus needs only 3 wires 2 signals and a ground so a 4 wire terminal with an added power terminal seems plausible. the two transistors and two large 120-ohm resistors are also consistent with a CAN driver
The second one probably is RS485, you can see that the traces for + and - are wide and come from elsewhere on the board, so they are probably power ...