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Component Inspection

Check Main relay

IG "OFF".
Disconnect the main relay.
Measure the resistance between battery power supply and control terminals of main relay. (Measurement "A")

Measure the resistance between battery power supply and power supply to PCM terminals of main relay. (Measurement "B")

Specification: 70 ~ 120 Ω

CONTINUITY SPECIFICATION

Terminal	Continuity
Battery power supply - Power supply to PCM	NO
Battery power supply - Main relay control	YES (Approx. 70 Ω ~ 120 Ω)

Fig 1: Measuring Resistance Between Battery Power Supply & Control Terminals Of Main Relay

Courtesy of HYUNDAI MOTOR CO.

Is the measured resistance within specification?
YES
1. Substitute with a known - good PCM and check for proper operation. If the problem is corrected, replace PCM and go to VERIFICATION OF VEHICLE REPAIR procedure.
NO
1. Substitute with a known - good Main relay and check for proper operation. If the problem is corrected, replace Main relay and go to VERIFICATION OF VEHICLE REPAIR procedure.
NOTE: There is a memory reset function on scantool that can erase optional parts automatically detected and memorized by PCM. After testing PCM on the vehicle, use this function to reuse the PCM on the others