Jump to content


Rx 330 Cooling Fan / A/c Issue Need Help To Diagnose - Please!


tjmc11

Recommended Posts

04 RX330. Cooling fan(s) were not operating as normal and thus a/c would not cool (due to pressure rise in system due to heat build up in condensor) at idle / stop. However, A/C would cool as normal when driving / moving due to air flow over condensor / radiator.

Tested fans (by hot wiring) and the main cooling fan (drivers side) was functional, while the auxillary / condenser fan (passenger) was not working properly (intermentant due to loose cnnection on MOTOR SIDE.

Purchased NEW Fan ECU (above fans, and acts as a ground relay if I am not mistaken). Connected main cooling fan to new ecu. Started motor, and brought up to temp. As I would bring RPM's up to 1500+ the main fan would kick on / off.

Connected condensor fan next. Turned on a/c in vehicle while at idle. Fan DID NOT COME ON. Turned off vehicle.

Disconnected condensor fan, left main fan connected for time being to go pick up new fan motor.

Replaced Fan Motor for condensor / auxillary fan.

Connected both main fan motor and auxillary motor to Fan ECU (New ECU). Started engine. Turned on a/c and FANS STILL DID NOT WORK, AND clutch for Compressor kept kicking on and off.

Tested ECU to see if it had current (positive +) running through it with test light on postive terminal on Fan ECU. Tested good for current for BOTH main fan and auxillary / condensor fan connections.

**This leads me to beleive that the ECU is not opening ground switch for some reason, or is unable to open a ground switch (could have been effected by original test after installing new ECU - see above).

PLEASE, SOMEONE, direct me what to check for next. Temp sensor?, a/c pressure sensor?, IS THERE A MAIN RELAY for the fans somewhere?

HELP HELP HELP!!!!!

Link to comment
Share on other sites

Hard to know what else to suggest. Strong logic. So here anther tact.

I'll tell you what I do first on my Porsche, Take out related relays (maybe ECU to) trlated to component and smack them on the ground. This can do two things, knock a stuck relay loose or dislodges some noncunductice crud from the contact surfaces. When you find the culprit, use you problem solving skills to take it apart and clean the contacts.

While your at it, every wire socket puled off should be pulled on and of several times to make sure a good connection made between the 2.

Hope it works, practically never fails on my car.

PK

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.



×
×
  • Create New...

Forums


News


Membership