Engine Cooling Symptom Diagnosis
| Condition | Possible Cause | Action |
|---|---|---|
| Engine overheats (It is in case that radiator fan operates) | Loose or broken water pump belt | Adjust or replace . |
| Not enough coolant | Check coolant level and add as necessary . | |
| Faulty thermostat | Replace . | |
| Faulty water pump | Replace . | |
| Dirty or bent radiator fins and/or A/C condenser fins | Clean or remedy . | |
| Coolant leakage on cooling system | Repair . | |
| Clogged radiator and/or A/C condenser | Check and replace radiator and/or A/C condenser as necessary . | |
| Faulty radiator cap | Replace . | |
| Improper ignition timing | Adjust . | |
| Dragging brakes | Adjust brake . | |
| Slipping clutch | Adjust or replace . | |
| Poor charge battery | Check and replace as necessary . | |
| Poor generation generator | Check and repair . | |
| ECT sensor faulty | Check and replace as necessary . | |
| Radiator cooling fan relay No.2 and/or No.3 faulty | Refer to RADIATOR COOLING FAN RELAY INSPECTION . | |
| Radiator fan motor faulty | Check and replace as necessary . | |
| A/C condenser cooling fan relay faulty | Check A/C condenser cooling fan relay (Refer to COMPRESSOR RELAY AND CONDENSER COOLING FAN RELAY INSPECTION: MANUAL TYPE ). | |
| A/C condenser cooling fan motor faulty | Check A/C condenser cooling fan motor (Refer to CONDENSER COOLING FAN INSPECTION: MANUAL TYPE ). | |
| ECM faulty | Check and replace as necessary . | |
| Wiring or grounding faulty | Repair as necessary . | |
| Equipped with too much electric load part | Dismount . | |
| Equipped with too much part to bumper air inlet | Dismount . | |
| A/C system faulty | Check A/C system (Refer to AIR CONDITIONING SYSTEM CHECK: MANUAL TYPE or AIR CONDITIONING SYSTEM CHECK: AUTOMATIC TYPE ). | |
| Power steering system faulty | Check power steering system (Refer to POWER STEERING (P/S) SYSTEM (IF EQUIPPED) INSPECTION ). | |
| EGR system faulty | Check EGR system (Refer to EGR SYSTEM INSPECTION (USING SUZUKI SCAN TOOL) ). | |
| IAC system faulty | Check IAC system (Refer to IDLE AIR CONTROL (IAC) SYSTEM CHECK ). | |
| Engine overheats (It is in case that radiator fan won't operate) | Fuse blown | Check 30A fuse of main fuse box and check for short circuit to ground . |
| Radiator cooling fan relay No.1 | Refer to RADIATOR COOLING FAN RELAY INSPECTION . | |
| ECT sensor faulty | Check and replace as necessary . | |
| Radiator cooling fan motor faulty | Refer to RADIATOR COOLING FAN ON-VEHICLE INSPECTION . | |
| Wiring or grounding faulty | Repair as necessary . | |
| ECM faulty | Check and replace as necessary . |
ENGINE COOLING SYMPTOM DIAGNOSIS CHART
Scheme 3
Thermostat Inspection
Reference: THERMOSTAT REMOVAL AND INSTALLATION
Scheme 4
- Make sure that air bleed valve (1) of thermostat is clean. Should this valve be clogged, engine would tend to overheat.
- Check to make sure that valve seat is free from foreign matters which would prevent valve from seating tight.
- Check thermostat seal (2) for breakage, deterioration or any other damage.
- Check thermostatic movement of wax pellet as follows: Immerse thermostat (1) in water, and heat water gradually. Check that valve starts to open at specific temperature. Temperature at which valve begins to open 80 - 84°C (176 - 183°F) Temperature at which valve become fully open 95 - 97°C (203°F) Valve lift More than 8 mm at 95°C (203°F)
If valve starts to open at a temperature substantially below or above specific temperature, thermostat unit should be replaced with a new one. Such a unit, if reused, will bring about overcooling or overheating tendency.
Scheme 5
Scheme 6
Scheme 7
- Check continuity between each terminals. If there is no continuity, replace radiator fan motor.
- Connect battery to radiator fan motor coupler as shown in figure, then check that the radiator fan motor operates smoothly, fan speed varies and that specified current. If radiator fan motor does not operate smoothly, replace motor. Radiator cooling fan motor specified current at 12 V LOW: 10 A maximum HIGH: 15 A maximum
Scheme 8
- Disconnect negative (-) cable at battery.
- Remove radiator cooling fan relay No.1 (1), No.2 (2) and No.3 (3) from relay box (4).
- Check that there is no continuity between terminal "C" and "B". If there is continuity, replace relay.
- Connect battery positive (+) terminal to terminal "B" of relay. Connect battery negative (-) terminal "A" of relay. Check continuity between terminal "C" and "D". If there is no continuity when relay is connected to the battery, replace relay.
Inspection
Check radiator for leakage or damage. Straighten bent fins, if any.
Engine Coolant Temp. Signal Inspection
Check engine coolant temp. signal referring to Step 3 of DTC P1709 (No. 51): ENGINE COOLANT TEMPERATURE AND BAROMETRIC PRESSURE SIGNAL CIRCUIT MALFUNCTION .
If check result is not satisfactory, check each wire harness, circuit connection and ECT sensor.
Scheme 9
Water Pump Inspection
Reference: WATER PUMP REMOVAL AND INSTALLATION
| CAUTION | Do not disassemble water pump. If any repair is required on pump, replace it as assembly. |
Scheme 10
Scheme 11
- Rotate water pump by hand to check for smooth operation. If pump does not rotate smoothly or makes abnormal noise, replace it.
- Inspect water pump (1) impeller (2) for damage. Replace as necessary.