Diagnosis - Suzuki Engine 2002 GRAND VITARA SQ420 Service Manual

6G-4 CRANKING SYSTEM (0.9 kW, 1.2 kW and 1.4 kW Reduction Type)
Possible symptoms due to starting system trouble would be as follows :
• Starting motor does not run (or runs slowly)
• Starting motor runs but fails to crank engine
• Abnormal noise is heard
Proper diagnosis must be made to determine exactly where the cause of each trouble lies.....in battery, wiring
harness, (including starting motor switch), starting motor or engine.
Do not remove motor just because starting motor does not run. Check following items and narrow down scope
of possible causes.
1) Condition of trouble
2) Tightness of battery terminals (including ground cable connection on engine side) and starting motor termi-
nals
3) Discharge of battery
4) Mounting of starting motor
Condition
Motor not running
Motor not running

Diagnosis

Possible Cause
No operating sound of magnetic switch
• Shift lever switch is not in P or N, or not
adjusted (A/T)
• Battery run down
• Battery voltage too low due to battery deteri-
oration
• Poor contact in battery terminal connection
• Loose grounding cable connection
• Fuse set loose or blown off
• Poor contacting action of ignition switch and
magnetic switch
• Lead wire coupler loose in place
• Open-circuit between ignition switch and
magnetic switch
• Open-circuit in pull-in coil
• Brushes are seating poorly or worn down
• Poor sliding or plunger and/or pinion
Operating sound of magnetic switch heard
• Battery run down
• Battery voltage too low due to battery deteri-
oration
• Loose battery cable connections
• Burnt main contact point, or poor contacting
action of magnetic switch
• Brushes are seating poorly or worn down
• Weakened brush spring
Burnt commutator
Layer short-circuit of armature
Crankshaft rotation obstructed
Correction
Shift in P or N, or adjust switch.
Recharge battery.
Replace battery.
Retighten or replace.
Retighten.
Tighten or replace.
Replace.
Retighten.
Repair.
Replace magnetic switch.
Repair or replace.
Repair.
Recharge battery.
Replace battery.
Retighten.
Replace magnetic switch.
Repair or replace.
Replace.
Replace armature.
Replace.
Repair.