code 18

possible causes
faulty right motor field circuit, faulty H bridge board, faulty logic card, faulty controller harness

how the code is triggered
when h bridge board detects over-current for right FET (transistor)
software checks following signal and detects fault when the signal is under 1V.
-R. Field Error (CN2-13)
Areas to check
disconnect battery plug, check right motor field cable terminals, logic card CN2-13 terminal and H bridge board CN2-16 terminal for abnormality.
If acceptable
-check continuity between following terminals. Right motor field cables
-logic card CN2-13 and CN2-63(neg)
If unacceptable
correct or replace cables.

If not shorted turn on key and confirm 18 is displayed.
Confirm voltage between CN2-13 and CN2-63(neg) with multimeter. If shorted correct or replace faulty circuit.

If 0v replace H-bridge board, If about 15v replace logic card.