Engine Cooling Systems Toyota Corolla VI

ELECTRIC COOLING FAN

Note. On models with A/C, electric cooling fans are also controlled by A/C system. See appropriate AIR CONDITIONING & HEATING article.

COOLING FAN QUICK TEST (CAMRY 4-CYL, CELICA, COROLLA)

1. Ensure engine coolant temperature is below 181°F (83°C). Turn ignition on. Fan motor should not run. If it does, check cooling fan relay, coolant temperature switch, and wiring.
2. With ignition on, unplug coolant temperature switch. Fan motor should operate. If not, check cooling fan relay, fan motor, engine main relay, fuse, and wiring.
3. Reconnect coolant temperature switch. Start engine and raise coolant temperature above 199°F (93°C). Fan motor should operate. If not, replace coolant temperature switch.

COOLING FAN QUICK TEST (CAMRY V6)

1. Ensure engine coolant temperature is below 185°F (85°C). Turn ignition on. Fan motor should not run. If it does, check cooling fan relay, coolant temperature switch, and wiring.
2. With ignition on, unplug radiator fan switch. Fan motor should operate. If not, check cooling fan relay, fan motor, engine main relay, fuse, and wiring.
3. Reconnect coolant temperature switch. Start engine and raise coolant temperature to 185-194°F (85-90°C). Fan motor should operate at low speed. If not, replace coolant temperature switch.
4. With engine on continue to raise coolant temperature above 194°F (90°C). Fan motor should operate at high speed. If not, replace coolant temperature switch.

COOLING FAN QUICK TEST (TERCEL)

1. Ensure engine coolant temperature is below 172°F (78°C) on carbureted engine, below 181°F (83°C) on fuel injected engine. Turn ignition on. Fan motor should not run. If it does, check cooling fan relay, coolant temperature switch, and wiring.
2. With ignition on, unplug coolant temperature switch. Fan motor should operate. If not, check cooling fan relay, fan motor, engine main relay, fuse, and wiring.
3. Reconnect coolant temperature switch. Start engine and raise coolant temperature above 192°F (89°C) on carbureted engine, above 201°F (94°C) on fuel injected engine. Fan motor should operate.
4. Allow coolant temperature to drop. Fan motor should stop when coolant temperature is below 172°F (78°C) on carbureted engine, below 181°F (83°C) on fuel injected engine. If not, replace coolant temperature switch.

COOLANT TEMP SWITCH TEST (CAMRY, CELICA, COROLLA, TERCEL)

1. Remove switch from vehicle. Coolant temperature switch is located in upper radiator hose coolant inlet on engine. Camry V6 engine uses a 2 terminal switch. Switch, on all other engines, has a single terminal.
2. Using ohmmeter, ensure continuity is correct between wire connector and switch body (switch terminals on Camry V6). Switch may be gradually heated in water for testing. See appropriate COOLANT TEMPERATURE SWITCH CONTINUITY or RESISTANCE table.

COOLANT TEMPERATURE SWITCH CONTINUITY (EXCEPT CAMRY V6) (1)

COOLANT TEMPERATURE SWITCH RESISTANCE (CAMRY V6)

MANIFOLD TEMPERATURE SENSOR TEST (LAND CRUISER)

Manifold temperature sensor is located on intake manifold (single Blue wire). Remove sensor from intake manifold. Heat sensor slowly in water while checking continuity between wire terminal and sensor body. See LAND CRUISER MANIFOLD TEMPERATURE SENSOR RESISTANCE table. Replace sensor if resistance is not as specified.

MANIFOLD TEMPERATURE SENSOR RESISTANCE (LAND CRUISER)

COOLING FAN RELAY TEST (CAMRY, CELICA, COROLLA, TERCEL)

Disconnect wiring harness from cooling fan relay. Cooling fan relay is located in engine compartment relay/fuse box. Check continuity between relay terminals as shown. (Scheme 1)or (Scheme 2).

Note. Camry V6 A/C fan relay No. 3 may be tested using Land Cruiser cooling fan motor relay test procedure.

Scheme 1

Scheme 2

COOLING FAN MOTOR RELAY TEST (LAND CRUISER)

Disconnect wiring harness from cooling fan motor relay. Cooling fan motor relay is located behind driver's side kick panel. Check continuity between relay terminals as shown. (Scheme 3)

Scheme 3

COOLING FAN RELAY CKT TEST (LAND CRUISER)

Disconnect wiring harness from cooling fan relay. Cooling fan relay is located behind driver's side kick panel. Check for continuity between terminals and ground under conditions specified. See LAND CRUISER COOLING FAN RELAY CIRCUIT TEST table. (Scheme 4)

COOLING FAN RELAY CIRCUIT TEST (LAND CRUISER)

Scheme 4

ENGINE MAIN RELAY TEST (CAMRY, CELICA, COROLLA, TERCEL)

Engine main relay supplies power to cooling fan relay. Disconnect wiring harness from cooling fan relay. Relay is located in engine compartment relay/fuse box. Check continuity between relay terminals as shown. (Scheme 5)

Scheme 5

IGNITION RELAY TEST (LAND CRUISER)

Disconnect wiring harness from ignition relay. Ignition relay is located under left side of instrument panel, in fuse/relay panel. Check continuity between relay terminals as shown. (Scheme 3)

COOLING FAN MOTOR TEST (CAMRY, CELICA, COROLLA, TERCEL)

Disconnect wiring harness from fan motor. Connect battery and ammeter to fan motor. Fan should operate smoothly and amperage draw should be within range. See COOLING FAN MOTOR AMPERAGE DRAW SPECIFICATIONS table.

COOLING FAN MOTOR TEST (LAND CRUISER)

Remove shroud from fan motor. Unplug fan motor. Connect 12-volt battery source and ammeter to fan motor terminals. Ensure fan motor rotates smoothly and current draw is 2.8-3.8 amps.

4-CYLINDER ENGINE COOLING FAN MOTOR AMPERAGE DRAW SPECIFICATIONS

6-CYLINDER & V6 ENGINE COOLING FAN MOTOR AMPERAGE DRAW SPECIFICATIONS

COOLING FAN ECU TEST (CAMRY V6)

Disconnect wiring harness from cooling fan ECU. Cooling fan ECU is located under right side of dash, behind glove box. Check for continuity between wiring harness terminals and ground under conditions specified. See CAMRY V6 COOLING FAN ECU CIRCUIT TEST table. (Scheme 6)

CAMRY V6 COOLING FAN ECU CIRCUIT TEST

Scheme 6