Thermo King 002008, Manual

Page: 52 / 155

Electrical Maintenance
52
4. Check for battery voltage at the 7EB and 7EC
terminals on the PSM. Battery voltage should
be present on one of these terminals when AC
voltage is present on L1, L2, and L3. If not,
replace the relays on the PSM with relays that
function properly and recheck the voltage on
the 7EB and 7EC terminals. If battery voltage
is not present, the PSM is faulty.
5. Check for battery voltage at the 7EB terminal
on MC1 and at the 7EC terminal on MC2.
Battery voltage should be present at one of
these terminals. If not, check the continuity of
the 7EB and 7EC wires.
6. Check the continuity of the RED wires on the
motor contactors. The RED wires must have
continuity.
7. Check the CH circuit at MC1 and MC2 for
continuity to a chassis ground. If the CH
circuits do not have continuity to a chassis
ground, check the CH wires.
8. Check the continuity of the BLK wires on the
motor contactors. The BLK wires must have
continuity.
9. If the CH circuits and BLK wires do have
continuity to CH, the contactor that has
battery voltage present at 7EB (MC1) or at
7EC (MC2) is faulty.