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Sonata (2.4L) & XG350

NOTE: The PCM/ECM control relay circuit between terminals No. 6 and 8 includes a diode. Continuity should be present from terminal No. 8 to terminal No. 6, but not from terminal No. 6 to terminal No. 8.
  1. Turn ignition off. Locate relay behind center console, under radio. Disconnect relay 8-pin harness connector and remove relay. Check for continuity between PCM/ECM control relay terminals No. 5 and 7, and between terminals No. 6 and 8. See Fig 1. If continuity is present, go to next step. If continuity is not present, replace PCM/ECM control relay. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Repair as necessary.
  2. Using a fused jumper wire, apply battery voltage to relay terminal No. 8. Using another fused jumper wire, connect terminal No. 6 to ground. Check for continuity between relay terminals No. 2 and 4. See Fig 1. If continuity is present, go to next step. If continuity is not present, replace PCM/ECM control relay.
  3. Using a fused jumper wire, apply battery voltage to relay terminal No. 7. Using another fused jumper wire connect terminal No. 5 to ground. Check for continuity between relay terminals No. 1 and 7. If continuity is present, relay is okay, go to next step. If continuity is not present, replace PCM/ECM control relay.
  4. Turn ignition off. Measure voltage between ground and PCM/ECM control relay harness connector terminal No. 2 (Orange wire) on Sonata or terminal No. 4 (Orange wire) on XG350. If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short between circuit PCM/ECM control relay and MAIN fuse (30-amp) located in engine compartment junction block. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Repair as necessary.
  5. Turn ignition off. Check for an open or short circuit between engine control relay connector terminals No. 7 (Pink wire) on Sonata or (Pink/Black wire) on XG350 and terminal No. 8 (Orange wire) on Sonata and XG350. If circuit is okay, go to next step. If circuit is not okay, repair open or short circuit in wires between engine control relay 8-pin harness connector terminals No. 7 and 8 and engine compartment junction block.
  6. Turn ignition on. Measure voltage between ground and engine control relay connector terminal No. 7 (Pink wire) on Sonata or (Pink/Black wire) on XG350 and terminal No. 8 (Orange wire) on Sonata and XG350. If battery voltage is present, go to next step. If battery voltage is not present, repair open or short in circuit between engine compartment junction block and ignition switch.
  7. Turn ignition off. Check for an open or short circuit in Gray wire between engine control relay 8-pin harness connector terminal No. 1 and fuel pump 6-pin harness connector terminal No. 5, and Gray wire between engine control relay 8-pin harness connector terminal No. 1 and 10-pin multipurpose check connector terminal No. 9. Multipurpose check connector is located under instrument panel, left of steering column. Perform repairs as necessary. If Gray wire circuits are okay, go to next step. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Repair as necessary.
  8. Turn ignition off. Disconnect PCM/ECM harness connector No. C44-1 (A/T) or No. C45-1 (Sonata M/T). Check for an open or short circuit in Green/Orange wire between engine control relay connector terminal No. 5 and PCM/ECM connector No. C44-1 terminal No. 21 or connector No. C45-1 terminal No. 8 (Sonata M/T). See Figure, Figure or Figure . Perform repairs as necessary. If Green/Orange wire is okay, on Sonata, go to next step. On XG350, go to step  10.
  9. Turn ignition off. Reconnect PCM/ECM harness connector. Check for an open or short circuit in Tan wire between ground connection and engine control relay connector terminal No. 6. Perform repairs as necessary, and ensure ground connection is clean and tight. If Tan wire is okay, go to step  12.
  10. On Sonata models equipped with M/T , go to next step. On Sonata and XG350 models equipped with A/T, check for continuity in Tan wire between engine control relay 8-pin harness connector terminal No. 6 and PCM/ECM harness connector No. C44-2 terminal No. 9. If continuity is present, go to step  12. If continuity is not present, repair open in Tan wire.
  11. If vehicle is equipped with M/T, check for continuity in Tan wire between engine control relay 8-pin harness connector terminal No. 6 and PCM/ECM harness connector No. C45-2 terminal No. 8. If continuity is present, go to next step. If continuity is not present, repair open circuit in Tan wire.
  12. On all models, turn ignition on. Measure voltage between ground and INJECTOR fuse (10-amp) located in engine compartment junction block. If battery voltage is present, inspection is complete. If battery voltage is not present, repair Pink wire between PCM/ECM control relay 8-pin harness connector terminal No. 4 and INJECTOR fuse (10-amp). On XG350, if Pink wire is okay, substitute known-good PCM/ECM, then recheck. If symptom or indication goes away, replace original PCM/ECM. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Repair as necessary.
Fig 1: Identifying PCM/ECM Control Relay Harness Connector Terminals (Sonata 2.4L & XG350)
G99A03471Courtesy of HYUNDAI MOTOR CO.
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