Your 1997-2001 3.0L V6 Toyota Camry comes equipped with two radiator fan switches. One is a two terminal switch located on the bottom tank of the radiator and the other is an one terminal switch located on the thermostat housing.
In this tutorial, I'll explain how to test the the two-terminal switch, also known as:
- Radiator Fan Switch 1.
- Water Temperature Switch 1.
- Coolant Temperature Switch 1.
Contents of this tutorial:
- Radiator Fan Switch Basics.
- Symptoms Of A Bad Radiator Fan Switch.
- Where To Buy The Radiator Fan Switch.
- TEST 1: Checking Radiator And Condenser Fan Fuses.
- TEST 2: Activating The Radiator And Condenser Fan Motors.
- TEST 3: Checking Fan Operation With The Engine Running (With A Scan Tool).
- TEST 4: Checking Fan Operation With The Engine Running (With A Infrared Thermometer).
- More 3.0L Toyota Camry Tutorials.
APPLIES TO: This tutorial applies to the following vehicles:
- 3.0L V6 Toyota Camry: 1997, 1998, 1999, 2000, 2001.
Wiring Diagrams: You can find the cooling fan motor wiring diagrams here:
- Cooling Fan Circuit Wiring Diagram (1997-1998 3.0L V6 Toyota Camry).
- Cooling Fan Circuit Wiring Diagram (1999-2001 3.0L V6 Toyota Camry).
The following tutorial will help you test Radiator Fan Switch 1 on the 1995-1996 3.0L V6 Toyota Camry:
Radiator Fan Switch Basics
Radiator Fan Switch 1 is the component that signals when to activate your Camry's radiator and condenser fans (with the A/C off). Here are the essential details you should know to test it successfully:
Location:
- Radiator Fan Switch 1 is located on the bottom tank of the radiator.
- The connector includes two wires: green with a white stripe (GRN/WHT) and blue with a white stripe (BLU/WHT).
How it works:
- Below 190°F: The switch stays closed, maintaining continuity between its two terminals. This prevents the radiator and condenser fans from activating, allowing the engine to warm up to its operating temperature.
- Above 208°F: The switch breaks the connection between the terminals, interrupting their continuity. This action activates both the radiator and condenser fans, drawing air across the radiator to help cool the engine.
There are several ways to test Radiator Fan Switch 1. In this tutorial, I'll share a simple, reliable method I've used for years. The best part? There's no need to remove the switch.
Symptoms Of A Bad Radiator Fan Switch
Over time, the radiator fan switch is gonna wear out and lose its ability to accurately monitor coolant temperature and/or trigger the radiator fan relays.
When this happens, the radiator cooling fans aren't gonna operate as they should, potentially causing the engine to overheat or creating other cooling system issues.
Here are some typical signs of a malfunctioning radiator fan switch:
- Engine overheats: The engine temperature climbs, particularly when idling or in heavy traffic, because the radiator fans aren't engaging to cool the engine.
- Fans not engaging: The radiator fans remain off past the coolant temp activation point of the radiator fan switch.
- Inconsistent fan operation: The fans operate irregularly or unpredictably due to erratic signals from the faulty switch.
- Fan Relays not activating: The radiator fan relays don't get the activation signal they need from the switch to activate the fans.
- Fans running nonstop: If the switch fails in an "open" position, the fans may run continuously, even when the coolant temperature is below 208°F. This leads to bad gas mileage and accelerates fan motor wear.
Where To Buy The Radiator Fan Switch
The coolant temperature switch (radiator fan switch) on the 1997-2001 3.0L Toyota Camry isn't an expensive part. The following links will help you comparison shop for it (and it's connector) and save a few bucks:
TEST 1: Checking Radiator And Condenser Fan Fuses
IMPORTANT: Before performing any tests on the radiator fan switch, you got to first verify that each fan motor's amperage draw is below 15 Amps. This simple test can be done using a multimeter. You can find the detailed instructions here:
We'll begin by checking the basics. The first step is to inspect the CDS Fuse (30A) and the RDI Fuse (30A) to make sure they're not blown. Both fuses are located in the engine compartment fuse/relay box.
Let's get started:
- 1
Locate the CDS Fuse (30A) in the under-hood fuse box of your Toyota Camry.
The CDS Fuse (30A) supplies power to the A/C condenser fan motor.
The condenser fan is the one located on the right (passenger) side of the radiator. - 2
Remove the fuse and check its condition.
- 3
Replace the fuse if blown with a fuse of the same rating (30A).
- 4
Locate the RDI Fuse (30A) in the under-hood fuse box of your Toyota Camry.
The RDI Fuse (30A) supplies power to the radiator fan motor.
The radiator fan is the one located on the left (driver) side of the radiator. - 5
Remove the fuse and check its condition.
- 6
Replace the fuse if blown with a fuse of the same rating (30A).
Let's interpret your test result:
CASE 1: Both fuses are OK. This is the correct and expected test result.
Your next step is to go to: TEST 2: Activating The Radiator And Condenser Fan Motors.
CASE 3: The CDS fuse was blown. This usually tells you one of two things:
- The A/C condenser fan motor has a high amperage draw.
- The amperage draw of both fans, when running, is greater than 30 Amps.
Replace the fuse with a fuse of the same rating. If you haven't done so, check the amperage draw of the fan motors. The following tutorial will show you how:
If the amperage draw is within the correct range, your next step is to go to: TEST 2: Activating The Radiator And Condenser Fan Motors.
CASE 3: The RDI fuse was blown. This usually tells you that the radiator fan motor has a high amperage draw. This high amperage draw will blow the fuse every time the radiator fan motor activates.
Replace the fuse with a fuse of the same rating. If you haven't done so, check the amperage draw of the radiator fan motor. The following tutorial explains how:
If the amperage draw is within the correct range, your next step is to go to: TEST 2: Activating The Radiator And Condenser Fan Motors.
TEST 2: Activating The Radiator And Condenser Fan Motors
So far, you've:
- Verified that each fan motor's amperage draw is below 15 Amps.
- Confirmed that the CDS and RDI fuses are not blown.
In this section, we’ll test the fan relays and motors by disconnecting the radiator fan switch and turning the key to the ON position (and engine OFF).
If 1) both radiator fan relays (1 and 2) are functioning properly, and 2) the wiring between the relays and cooling fans is intact, both fans should activate.
CAUTION: Accessing the radiator fan switch on the 1997-2001 3.0L Camry requires lifting the vehicle. Always use jack stands to keep the vehicle securely elevated —never rely on the jack alone!
Let's get going:
- 1
Locate the radiator fan switch.
- 2
Disconnect the radiator fan switch from its electrical connector.
- 3
Turn the key to the ON position but don't crank or start the engine.
- 4
Both fans should turn ON.
Let's take a look at what your test results mean:
CASE 1: Both fan motors turned ON. This is the correct and expected test result.
With this result, you've confirmed that the entire electrical circuit for the fan motors is working properly. Specifically, this means:
- The fan relays are functioning correctly.
- There are no wiring issues between the radiator fan switch and the fan relays or between the fan relays and the fan motors.
Your next step:
If you have a generic scan tool with "live data" functionality, go to: TEST 3: Checking Fan Operation With The Engine Running (With A Scan Tool).
If you DON'T have a generic scan tool with "live data" functionality, go to: TEST 4: Checking Fan Operation With The Engine Running (With A Infrared Thermometer).
CASE 2: Both fan motors DID NOT turn ON. This test result usually points to a bad radiator fan relay (and there's 3 of them).
Testing the radiator fan relays is your next step. Although it's beyond the scope of this tutorial, you'll need to verify whether one or more of the relays are faulty.
CASE 3: The radiator fan motor DID NOT turn ON. This result indicates a problem isolated to the radiator fan motor circuit (wiring), only if you have:
- The amperage draw of the radiator fan motor is under 15 Amps.
- Checked its operation by applying 12 Volts and Ground from the battery.
Although it's beyond the scope of this tutorial, your next step is to:
- Check for an open-circuit problem in the blue (BLU) wire between the radiator fan motor connector and Radiator Fan Relay 1.
- Check for an open-circuit problem in the white with black stripe (WHT/BLK) wire between the radiator fan motor connector and chassis Ground.
CASE 4: The condenser fan motor DID NOT turn ON. This result indicates a problem isolated to the condenser fan motor circuit (wiring), only if you have:
- Tested the amperage draw of the condenser fan motor.
- Checked its operation by applying 12 Volts and Ground from the battery.
Although it's beyond the scope of this tutorial, your next step is to:
- Check for an open-circuit problem in the black with red stripe (BLK/RED) wire between the condenser fan motor connector and CDS Fuse (30A).
- Check for an open-circuit problem in the red (RED) wire between the condenser fan motor connector and Radiator Fan Relay 2.