Cooling system fan not working - 1994 Plymouth Sundance

Both radiator cooling fans are running all the time ? Key off ? The cooling fan opperation
HOW they work
Cooling Fan Control
The engine cooling fan system consists of 2 cooling fans and 3 relays. The relays are powered by the battery positive voltage circuit and controlled by a switched ground from the powertrain control module (PCM).
During low speed operation, the PCM supplies the ground path for the low speed cooling fan relay through the low speed cooling fan relay control circuit. This energizes the cooling fan low relay coil, closes the relay contacts, and supplies battery positive voltage from the COOL FAN LO fuse through the cooling fan motor supply voltage circuit to the cooling fan. During high speed operation the PCM supplies the ground path for the cooling fan low relay through the low speed cooling fan relay control circuit. After a 3-second delay, the PCM supplies a ground path for the cooling fan high relay and the s/p cooling fan relay through the high speed fan relay control circuit.
The PCM commands the fan on under the following conditions:
• Engine coolant temperature exceeds approximately 98°C (208°F) Low Fan Speed
• Engine coolant temperature exceeds approximately 102°C (216°F) High Fan Speed
• A/C refrigerant pressure exceeds 361 kPa (52 psi) Low Fan Speed
• A/C refrigerant pressure exceeds 2100 kPa (300 psi) High Fan Speed
• When the engine coolant temperature exceeds 112°C (234°F) at key off, the fan high speed will run for up to 300 seconds. If within that time frame 102°C (216°F) is reached then fan speed will change from high to low speed. If within that time frame 99°C (210°F) is reached then fan speed will change from low to off.
The PCM commands the fan off under the following conditions:
• A/C is requested and engine speed exceeds 6,240 RPM
• Engine coolant temperature exceeds approximately 99°C (210°F) turns the cooling fans from low to off.

sounds like one of the relays are stuck closed .

Cooling Fan Always On
Step
Action
Yes
No
Schematic Reference: Engine Cooling Schematics , HVAC Schematics in HVAC Systems - Manual
Connector End View Reference: Cooling System Connector End Views
DEFINITION: One or both engine cooling fan motors run continuously in high or low speed.
1
Did you perform the Diagnostic System Check - Vehicle?
Go to Step 2
Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2
Install a scan tool.
Turn ON the ignition, with the engine OFF.
With a scan tool, command the Fans Low Speed ON and OFF.
Are one or both cooling fans ON?
Go to Step 3
Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
3
Are both cooling fans running continuously?
Go to Step 4
Go to Step 6
4
Are both cooling fans running continuously in high speed?
Go to Step 5
Go to Step 7
5
Test the low reference circuit of the A/C refrigerant pressure sensor for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 18
Go to Step 14
6
Important: The S/P relay is located under the front bumper on the drivers side of the vehicle.
Remove the cool fan S/P relay.
Did the right cooling fan turn OFF?
Go to Step 10
Go to Step 8
7
Remove the cool fan LOW relay.
Did the cooling fans turn OFF?

What engine does it have ?

Cooling Fan Control 2.0L
The engine cooling fan is a variable speed fan. The engine control module (ECM) controls the fan speed by sending a pulse width modulated (PWM) signal to the cooling fan control module. The cooling fan control module varies the voltage drop across the engine cooling fan motor in relation to the PWM signal. The cooling fan speed can be adjusted from 10 percent to 94 percent duty cycle. 94 percent is considered high speed fan.
Cooling Fan Control 2.2L or 2.4L
The engine cooling fan system consists of one cooling fan and one relay. Voltage is supplied to the relay through a fuse. The engine control module (ECM) controls the fan operation by grounding the cool fan relay control circuit. When the cool fan relay is energized, voltage is delivered to the cooling fan motor. The cooling fan motor is grounded through its own ground circuit.
When the request for fan activation is withdrawn, the fan may not turn OFF until the ignition switch is moved to the OFF position or the vehicle speed exceeds approximately 10 mph. This is to prevent the fan from cycling ON and OFF excessively at idle.


Just one speaker doesn't work ? Do you know how to do automotive electrical testing ? That's how to find both your problems . Speakes work by electrical inpluse's . The A/C radiator ( condenser ) fan also works by B+ voltage through a fuse an a relay , controlled by the engine electronic control module or PCM - powertrain control module . When you push the A/C turn on button , it sends a signal to the PCM . The PCM will then energize the radiator fan relay turning on the fan . Check fuse in the under hood fuse box , If the fuse is blown you have a electrical short , too much current flow . Plus if the PCM sees too much pressure in the A/C system it will not let the A/C work .

Hi Maria , The A/C system wouldn't keep the fans from running but none working cooling fans will keep the A/C from working ! This is a fairly complex system if your not familiar with this sort of thing ! I will add the description from the factory service manual.
Cooling Fan Control - Two Fan System
The engine cooling fan system consists of 2 electrical cooling fans and 3 fan relays. The relays are arranged in a series/parallel configuration that allows the powertrain control module (PCM) to operate both fans together at low or high speeds. The cooling fans and fan relays receive battery positive voltage from the underhood fuse block.
During low speed operation, the PCM supplies the ground path for the low speed fan relay through the low speed cooling fan relay control circuit. This energizes the low speed fan relay coil, closes the relay contacts, and supplies battery positive voltage from the low fan fuse through the cooling fan motor supply voltage circuit to the left cooling fan. The ground path for the left cooling fan is through the cooling fan s/p relay and the right cooling fan. The result is a series circuit with both fans running at low speed.
During high speed operation the PCM supplies the ground path for the low speed fan relay through the low speed cooling fan relay control circuit. After a 3 second delay, the PCM supplies a ground path for the high speed fan relay and the cooling fan s/p relay through the high speed cooling fan relay control circuit. This energizes the cooling fan s/p relay coil, closes the relay contacts, and provides a ground path for the left cooling fan. At the same time the high speed fan relay coil is energized closing the relay contacts and provides battery positive voltage from the high fan fuse on the cooling fan motor supply voltage circuit to the right cooling fan. During high speed fan operation, both engine cooling fans have there own ground path. The result is a parallel circuit with both fans running at high speed.
Do you have a check engine light lit ? The thing to do would have it check at the dealer or a ASE certified repair facility ! They could hook up a advanced scan tool an diagnose fairly quick ! Or you could find a wiring diagram an try testing with a volt meter yourself ! But watch yourself so you don't short out the PCM - engine computer !

check cooling fans fuse and relay.bad engine coolant temperature sensor will cause coolant fans not to turn on.if AC system not working with no refrigerant in the system cooling fans wont turn on when you turn on the AC.problem in PCM will cause fans not to turn on.

FAN NOT WORKING

It can be issue with faulty motor or its faulty fan control relay.

Bother are to be inspected.

Test volt at fan relay and fan motor.

-------------

For more help, I suggest you to go through the troubleshooting links mentioned below:-----

Click the link below: ------

How to replace Cooling Fan on Acura Car models?

http://repairhelpcenter.blogspot.com/2011/11/how-to-replace-cooling-fan-on-acura-car.html

--------------

OBD Code P1490 low speed fan relay ckt open-short

http://schematicsdiagram.blogspot.com/2012/11/obd-code-p1490-low-speed-fan-relay-ckt.html

---------------

Engine cooling components working?

http://repairhelpcenter.blogspot.com/2011/11/engine-cooling-components-working.html

----------

How does Vehicles Engine cooling system works?

http://repairhelpcenter.blogspot.com/2011/11/how-does-vehicles-engine-cooling-system.html

---------------

Hyundai Sonata cooling fan not working

http://schematicsdiagram.blogspot.in/2012/02/hyundai-sonata-cooling-fan-not-working.html

-------------

Fuel pump relay and cooling fan relay troubleshooting on 1997 ford thunderbird?

http://repairhelpcenter.blogspot.com/2011/10/fuel-pump-relay-and-cooling-fan-relay.html

--------------

Fan belt routing diagram for 2004 Volkswagen Jetta?

http://carbeltrouting.blogspot.com/2011/12/fan-belt-routing-diagram-for-2004.html

---------

Timing belt, drive belt, serpentine belt, accessory belt, fan belt, engine belt routing diagrams for all types of car models?

http://carbeltrouting.blogspot.in/2012/02/timing-beltdrive-beltserpentine.html

-------------

A/C, heater, defroster fan, not working?

http://technoanswers.blogspot.in/2012/02/ac-heater-defroster-fan-not-working.html

---------

Blower fan not running on Isuzu trooper?

http://technoanswers.blogspot.in/2012/02/blower-fan-not-running-on-isuzu-trooper.html

---------

How to replace blower motor fan assembly on 2000 GMC Yukon?

http://repairhelpcenter.blogspot.com/2012/01/how-to-replace-blower-motor-fan.html

----------

Heater AC or defroster fan not working on KIA?

http://technoanswers.blogspot.in/2012/02/heater-ac-or-defroster-fan-not-working.html

------------

These will help.

Thanks.

It can be issue with faulty motor or its faulty fan control relay.
Bother are to be inspected.Test volt at fan relay and fan motor.-------------
For more help,i suggest you to go through the troubleshooting links mentioned below:-----Click the link below:------

How to replace Cooling Fan on Acura Car models?

http://repairhelpcenter.blogspot.com/2011/11/how-to-replace-cooling-fan-on-acura-car.html
--------------

OBD Code P1490 low speed fan relay ckt open-short
http://schematicsdiagram.blogspot.com/2012/11/obd-code-p1490-low-speed-fan-relay-ckt.html
---------------

Engine cooling components working?

http://repairhelpcenter.blogspot.com/2011/11/engine-cooling-components-working.html

----------

How does Vehicles Engine cooling system works?

http://repairhelpcenter.blogspot.com/2011/11/how-does-vehicles-engine-cooling-system.html

---------------

Hyundai Sonata cooling fan not working

http://schematicsdiagram.blogspot.in/2012/02/hyundai-sonata-cooling-fan-not-working.html

-------------

Fuel pump relay and cooling fan relay troubleshooting on 1997 ford thunderbird?

http://repairhelpcenter.blogspot.com/2011/10/fuel-pump-relay-and-cooling-fan-relay.html
--------------

Fan belt routing diagram for 2004 Volkswagen Jetta?

http://carbeltrouting.blogspot.com/2011/12/fan-belt-routing-diagram-for-2004.html
---------

Timing belt, drive belt, serpentine belt, accessory belt, fan belt, engine belt routing diagrams for all types of car models?

http://carbeltrouting.blogspot.in/2012/02/timing-beltdrive-beltserpentine.html
-------------

A/C, heater, defroster fan, not working?

http://technoanswers.blogspot.in/2012/02/ac-heater-defroster-fan-not-working.html
---------

Blower fan not running on Isuzu trooper?

http://technoanswers.blogspot.in/2012/02/blower-fan-not-running-on-isuzu-trooper.html
---------

How to replace blower motor fan assembly on 2000 GMC Yukon?

http://repairhelpcenter.blogspot.com/2012/01/how-to-replace-blower-motor-fan.html
----------

Heater AC or defroster fan not working on KIA?

http://technoanswers.blogspot.in/2012/02/heater-ac-or-defroster-fan-not-working.html
------------These will help.Thanks.

If the fan not turning on when car engine getting hot,then car will notice overheating.Click this link below for troubleshooting:---http://technoanswers.blogspot.in/2012/02/car-running-hot.html--------To know how engine cooling system works ,click the link below :----Engine cooling components working?

http://repairhelpcenter.blogspot.com/2011/11/engine-cooling-components-working.html

------------------
How does Vehicles Engine cooling system works? http://repairhelpcenter.blogspot.com/2011/11/how-does-vehicles-engine-cooling-system.html
------------How to Replace Engine cooling Fan:-- http://repairhelpcenter.blogspot.com/2011/11/how-to-replace-engine-cooling-fan-on.html
-----------Replace Fan Relay but still Radiator cooling fans not working? http://schematicsdiagram.blogspot.com/2011/12/replace-fan-relay-but-still-radiator.html
----------DIC says "COOLING FAN FAULT"? http://schematicsdiagram.blogspot.com/2011/12/dic-says-cooling-fan-fault.html
---------Where Is Radiator Fan relay and Fuse Located?

http://schematicsdiagram.blogspot.com/2011/12/where-is-radiator-fan-relay-and-fuse.html

--------

This will help.

Thanks.

For radiator replacement procedure and radiator problem troubleshooting. I suggest you to click the link below and follow the detailed procedure :-----

------------

How to Replace Engine cooling Fan on car? http://repairhelpcenter.blogspot.com/2011/11/how-to-replace-engine-cooling-fan-on.html

------------

Engine makes noise and Cooling Fan belt Breaks? http://howtobyme.blogspot.com/2011/12/engine-makes-noise-and-cooling-fan-belt.html

-----------

Replace Fan Relay but still Radiator cooling fans not working? http://schematicsdiagram.blogspot.com/2011/12/replace-fan-relay-but-still-radiator.html

--------

Cooling fan relays location? http://technoanswers.blogspot.in/2012/02/cooling-fan-relays-location-on-1998.html----------DIC says "COOLING FAN FAULT"? http://schematicsdiagram.blogspot.com/2011/12/dic-says-cooling-fan-fault.html
------------

How to replace radiator Cooling Fan?

http://repairhelpcenter.blogspot.com/2011/11/how-to-replace-cooling-fan-on-acura-car.html

---------------
Engine cooling components working?

http://repairhelpcenter.blogspot.com/2011/11/engine-cooling-components-working.html

-------------
How does Vehicles Engine cooling system works? http://repairhelpcenter.blogspot.com/2011/11/how-does-vehicles-engine-cooling-system.html

----------

cooling fan not working http://schematicsdiagram.blogspot.in/2012/02/hyundai-sonata-cooling-fan-not-working.html----------- Fuel pump relay and cooling fan relay troubleshooting? http://repairhelpcenter.blogspot.com/2011/10/fuel-pump-relay-and-cooling-fan-relay.html

----------
Why Transmission fluid leaks near radiator?

http://repairhelpcenter.blogspot.in/2012/02/transmission-fluid-leaks-near-radiator.html

----------
Transmission fluid leaking?

http://technoanswers.blogspot.in/2012/02/ford-windstar-transmission-fluid.html

-------------
How to replace Radiator?

http://repairhelpcenter.blogspot.com/2011/11/how-to-replace-radiator-on-audi-and-vw.html

----------
HOW TO REPLACE AN UPPER RADIATOR HOSE

http://schematicsdiagram.blogspot.com/2011/07/how-to-replace-upper-radiator-hose.html

------------
HOW TO REPLACE A LOWER RADIATOR HOSE

http://schematicsdiagram.blogspot.com/2011/07/how-to-replace-lower-radiator-hose.html

-------------
How to replace Radiator on Car models?

http://repairhelpcenter.blogspot.com/2011/11/how-to-replace-radiator-on-acura-car.html

------------
How to flush cars radiator?

http://repairhelpcenter.blogspot.com/2011/11/how-to-flush-cars-radiator.html

--------
HOW TO PRESSURE TEST A RADIATOR AND CAP

http://schematicsdiagram.blogspot.com/2011/07/how-to-pressure-test-radiator-and-cap.html

----------------
HOW TO REPLACE A RADIATOR

http://schematicsdiagram.blogspot.com/2011/07/how-to-replace-radiator.html
------------------

HOW TO REPLACE A RADIATOR SUPPORT

http://schematicsdiagram.blogspot.com/2011/07/how-to-replace-radiator-support.html

-----------

This details will help.

Thanks.

Change the thermostat and bleed the ir from the cooling system,then ,if the cooling fans do not come on,check the relay module under the cooling fans on drivers side,they are bad to go out,but if there is air in the cooling system,the cooling fans will not come on.

Fifteen minutes! you have bigger problems than only the fans the fans are controlled by a thermo switch that is heated by the coolant, If you have no coolant the sensor cannot activate But fifteen minutes seems like you may have a headgasket problem and steam cannot heat the coolant sensor.OperationNotesThe electric cooling fan operates when the engine cooling temperature exceeds a certain value. The cooling fan on this engine is controlled by the Powertrain Control Module (PCM) . The PCM turns the cooling fan ON by grounding the coil of the cooling fan relays when certain conditions are met. When the A/C is requested, the cooling fan will also be turned ON.

Power for the cooling fan motors are supplied through Maxifuses(R). The cooling fan relays are energized when current flows from the fuses in the Underhood Accessory Wiring Junction Block, and through the relay coils to ground through the PCM. The Coolant Fan 1 Relay Control Circuit is grounded for low speed fans operation. During low speed fans operation, both fans run at a slow speed. The Coolant Fan 1 Relay Control Circuit is grounded for high speed operation. During high speed fans operation, both fans run at high speed.

IMPORTANT: When certain Diagnostic Trouble Codes (DTCs) are present, the PCM may command the cooling fans to run all the time. Perform the A Powertrain On Board Diagnostic (OBD) System Check prior to diagnosing the engine cooling fans.

For more information regarding the Charging System, refer to Charging System Description , and Charging System Circuit Description in Starting and Charging.

If a problem that involves the low speed cooling fan relay control circuit exists, DTC P0480 Cooling Fan Relay 1 Control Circuit should set. If the problem affects the high speed cooling fan relay control circuit, DTC P0481 Cooling Fan Relay 2 Control Circuit should set. A problem with the ECT sensor should set DTC P0117 Engine Coolant Temperature (ECT) Sensor Circuit Low Voltage, DTC P0118 Engine Coolant Temperature (ECT) Sensor Circuit High Voltage, DTC P1114 Engine Coolant Temperature (ECT) Sensor Circuit Intermittent Low Voltage, DTC P1115 Engine Coolant Temperature (ECT) Sensor Circuit Intermittent High Voltage. Any of these DTCs will affect cooling fan operation and should be diagnosed before using the Electric Cooling Fan Diagnosis.

For more information regarding the Cooling System refer to Engine Cooling Fan Description - Electric, and Cooling System Description in Cooling System.


Here is the electrical schematic and how it all is suppose to work,
If you need any further help please contact me Thank you,Randy If you find this information helpful please give me a good rating

www.aceautomotive1.com