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Home >> Jeep >> 2008 >> Grand Cherokee Laredo, 3.0 M, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Diesel - DTCS P068A To P2009 >> P1649-Glow Plug Module Power Supply Circuit >> Possible Causes

Possible Causes

Possible Causes 
INTERMITTENT DTC
(A15) FUSED ASD RELAY OUTPUT CIRCUIT OPEN OR HIGH RESISTANCE
(Z921) GROUND CIRCUIT OPEN OR HIGH RESISTANCE
GLOW PLUG MODULE
ENGINE CONTROL MODULE (ECM)

Always perform the PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding.