Overheating.
#1
02-10-2012, 08:45 AM
Overheating.
Hey guys. Im looking for a little help with my 92 v6 camry. Its overheating. 
Everything was fine until yesterday sitting at the light. I noticeed the dash gauge going up and it was getting hott. When i started to drive it went back down to normal. I got home and checked the level and it was good. Also the overflow was fine. I did notice the fan was turning really slow. Slow enough i could stop it with my hand. So my question is where the hell do i start. I know the fan is run off the ps fluid. And there is a couple sensors and a relay somewhere. 
This is my first Toyota so im new with these cars. Any help would be great.
Everything was fine until yesterday sitting at the light. I noticeed the dash gauge going up and it was getting hott. When i started to drive it went back down to normal. I got home and checked the level and it was good. Also the overflow was fine. I did notice the fan was turning really slow. Slow enough i could stop it with my hand. So my question is where the hell do i start. I know the fan is run off the ps fluid. And there is a couple sensors and a relay somewhere. This is my first Toyota so im new with these cars. Any help would be great.
#2
02-10-2012, 11:40 AM
Suggest for starters you pickup a Haynes service manual or other to troubleshoot the fan system. The system may have hydraulic not electric fans.
If so a cooling fan computer controls a hydraulic valve to control fan operation.
Check the hydraulic fluid level in the system reservoir near the pump which is on the passengers side of the engine. If low it uses the same fluid as the trans.
The fans should turn on when the AC compressor cycles on, make sure this is happening.
The coolant temp sensor is on the passengers side of the engine on the radiator side of the pump.
If so a cooling fan computer controls a hydraulic valve to control fan operation.
Check the hydraulic fluid level in the system reservoir near the pump which is on the passengers side of the engine. If low it uses the same fluid as the trans.
The fans should turn on when the AC compressor cycles on, make sure this is happening.
The coolant temp sensor is on the passengers side of the engine on the radiator side of the pump.
Last edited by toyomoho; 02-11-2012 at 11:55 PM.
#3
02-10-2012, 11:46 AM
Thank you. This just happend last night. Im goin to get a Haynes on my way home from work. It has the hydraulic fan set. That i know for sure. Like i mentioned im new with these cars and any and all advice/help is appreciated.
#5
02-11-2012, 11:09 PM
The chilton book was worthless. Nothing in it on the hydo setup for the fan. I ran it up to temp today and it didn't overheat. But that was in the driveway. The fan never changed speeds. I tried the jumper method a read in another to test the fan. Nothing. Gonna play with it tomorrow again.Also when I turned on the AC the fan did not change.
Last edited by Pushrod91; 02-11-2012 at 11:20 PM.
#6
02-12-2012, 12:04 AM
Were these connections OP1 and E1?
The Fan control unit controls power to the solenoid in response to the coolant temp sensor.
Issues could be the solenoid is not being powered, stuck, low system pressure, clogged oil filter (location on hose near upper part of radiator, bad pump motor.
You may be able to feel if the solenoid is being powered, check for a tight fan motor, Pressure should be 142-284 psi at idle.
The Fan control unit controls power to the solenoid in response to the coolant temp sensor.
Issues could be the solenoid is not being powered, stuck, low system pressure, clogged oil filter (location on hose near upper part of radiator, bad pump motor.
You may be able to feel if the solenoid is being powered, check for a tight fan motor, Pressure should be 142-284 psi at idle.
#7
02-13-2012, 09:02 AM
Yes it was the 0P1 and E1. That was the connector on the passenger side in the engine compartment. I jumped em and no change in fan. Also turned on the AC and no change. Im trying to find a book that actully explains how this system works and where everything is located at. Im having no luck. LOL. I check the fuses in the power box on the drivers side and all look ok. Theres only one relay in the little box on the drivers side in the engine compartment. Im assuming thats the relay for the fan system.
Last edited by Pushrod91; 02-13-2012 at 09:07 AM.
#8
02-13-2012, 04:10 PM
As even the service manual provides little info you may have trouble finding this.
The cooling fan ECU is under the dash, passengers side. May need to remove the glove box to access.
The engine coolant sensor is on the passengers side of the engine on the water pump intake manifold.
The cooling fan ECU is powered from the ECU-IG fuse. Has 9 wires.
Solenoid valve is yel and yel/blue.
Water temp sensor blue/yel and blue/white. Blue/white wire also goes to the box where you connected the two terminals thus might be one of the wire connected.
Brown is ground (located right hand intake manifold).
Blue/red is A/C pressure switch-turn fans on if pressure is too high.
Black goes to igniter.
Blue to engine ECU
Based on inputs from AC switch (not the one that turns on the system), engine ECU (most likely the engine computer tells the fan ECU the A/C is on), coolant system sensor and maybe the TPS (engine at idle), the solenoid on the hydraulic system opens or closes. If open the fan runs.
The manual state the solenoid adjusts flow to control speed thus it may be more then an on/off valve otherwise why run two wires and not a power wire and ground wire.
Jumping the connectors much drive the solenoid full open.
There are no relays to control the solenoid, just the fan ECU.
The pump and motor are oscillating rotor in design like an engine oil pump, no separate blades, etc.
The cooling fan ECU is under the dash, passengers side. May need to remove the glove box to access.
The engine coolant sensor is on the passengers side of the engine on the water pump intake manifold.
The cooling fan ECU is powered from the ECU-IG fuse. Has 9 wires.
Solenoid valve is yel and yel/blue.
Water temp sensor blue/yel and blue/white. Blue/white wire also goes to the box where you connected the two terminals thus might be one of the wire connected.
Brown is ground (located right hand intake manifold).
Blue/red is A/C pressure switch-turn fans on if pressure is too high.
Black goes to igniter.
Blue to engine ECU
Based on inputs from AC switch (not the one that turns on the system), engine ECU (most likely the engine computer tells the fan ECU the A/C is on), coolant system sensor and maybe the TPS (engine at idle), the solenoid on the hydraulic system opens or closes. If open the fan runs.
The manual state the solenoid adjusts flow to control speed thus it may be more then an on/off valve otherwise why run two wires and not a power wire and ground wire.
Jumping the connectors much drive the solenoid full open.
There are no relays to control the solenoid, just the fan ECU.
The pump and motor are oscillating rotor in design like an engine oil pump, no separate blades, etc.
#9
02-14-2012, 08:24 PM
Toyo thank you for your detailed post. Much appreciated. :-). Think I narrowed it down to the violent temp switch? The 2 wire sensor just under the alternater. I umpuged it and the fan kicked back up to normal. Tried to find one today and all the parts only had the one sensor by the thermastat houseing. Have to wait till tomorrow to get one. Ill post back to let you know the results. Again toyot jthank you for your help.