KC1 DTC P1391 AND P1395 RIGHT BANK, P1393 AND P1396 LEFT BANK AND P1994 CENTER MONITORING CIRCUIT. Both DTCs P1391 and P1393 together will set when the monitor indicates that all eight glow plugs are not being powered. An open in all glow plug circuits (shorted wire), the glow plug relay(faulty or inoperable), glow plugs(not working), fusible links or all three monitoring circuits could be the possible causes.
You can check for wiring chaffs yourself in the wiring circuitry for the glow plugs.Also check all fuses and relays that pertain to the glow plugs.
You will then need a diagnostic machine that can moniter PIDS to further diagnose any further problems.
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