James Matteu Posted June 22, 2007 Share Posted June 22, 2007 1997 Accord V6 (C27A 2.7L SOHC PGM-Fi 24 valves) Electrical Problem : Air Recirculation System : Blower function About two months ago, I noticed as I started my car, the blower would not function. I checked the fuse and it was fine. Shortly thereafter, I noticed the blower would work intermittently. The blower seemed to either come on right away and stay on, or not come on at all and stay off. In the latter, all switch settings were tried and all equally failed. About one month ago, I changed the blower motor relay: Mitsubishi RC-2225 with Honda OEM ($54.00). The blower came on immediately, but was noticeably weaker than ever before. About two weeks ago, I noticed the blower would operate at a speed slower than the lowest setting when set in the highest position. Furthermore, if switched to the lowest position (just above off), the blower would slow to a stop and not come on again. About one week ago, I hard wired the blower motor to my car batter with alligator clips and the thing nearly took my arm off it came on so fast. Then I measured the resistance of the blower resistor. I had trouble interpreting the reading since I have an analogue meter and was in an awkward position under the dash. Ideas: I don’t think it’s the switch, because I can select different blower speeds when the blower functions (albeit slower than normal). I don’t think it is the resistor since I believe it should either fail or work. If and when the resistor does fail, I should lose one speed, not all of them, and the resistor should not start working again after failing. I know it is not the motor, and not the relay, see above. Something is either reducing the voltage going to the blower motor or increasing resistance on the circuit without affecting the voltage. There could be a voltage drop, but I want to say it is more likely something is getting hot and increasing resistance between the motor and the battery. Please help me FIND THE SOURCE OF THIS PROBLEM!!!!!!!! Does anyone see something I need to focus on? Anything above I may have done incorrectly or need to revisit? If your comments are not serious, they better be serious attempts to cheer me up. It’s getting hot in Florida. In case anyone is thinking about it, there is no satisfaction in replacing the entire harness, motor, fuse box, relays and switches. That’s the punk’s way out. Link to comment Share on other sites More sharing options...
James Matteu Posted July 2, 2007 Author Share Posted July 2, 2007 I was looking over the schematic this past weekend and began to suspect a poor ground, but there are about 5 systems all sharing the same ground as the air recirculation system. I don't feel this is a valid concern but was inspired to re-check the under dash fuse box and the check the engine bay fuse box. I checked the 30A and 40A fuses in my engine bay, they were fine; looked new. Again, I checked the #7 fuse for the blower in the under dash fuse box, it was fine; looked new. This morning I started my car with the blower off. I then decided to see if the blower would work, so I turned the selector switch to speed 4 and the blower came on strong. I selected the different speeds (1, 2, and 3) and all worked properly. With the speed set to 1, I pressed the air recirculation button and the door closed cutting off outside air. I then changed the speed to 4 and pressed the A/C button and my compressor came on; I nearly froze it was so cold in my car. I then turned the blower to the off position and my blower turned off and the A/C compressor switched off. I then turned the selector back to the 4th speed setting and the blower did not switch on; I could hear the A/C compressor switch on. I am now even more confident the blower resistor and all connections are in good working order. Sometime this week, I will buy some mini-alligator clips to test the switch since all other parts of the system appear to function consistently. The Helm Publishing manual instructs the following: 1) remove switch cluster, 2) with voltage on, ground the pins leading to the blower resistor one by one, 3) observe blower response. If I am able to turn the blower on with this procedure, the switch will be relatively isolated as a possible source of this problem. I will then check the ohms coming through the switch in each setting while jostling it to see that all connections are good. If I have poor contact, the switch may be internally corroded or damaged. I will keep this thread updated. Perhaps someone will respond to this thread with a cleaver inexpensive solution. Link to comment Share on other sites More sharing options...
crxtacy Posted July 3, 2007 Share Posted July 3, 2007 when thr problem happens again,check power going to the blower resistor .If your getting power going there, more than likely the blower resistor is failing. If it happens after its been blowing for awhile then it starts acting up, i believe so it is the blower resistor . Link to comment Share on other sites More sharing options...
James Matteu Posted July 3, 2007 Author Share Posted July 3, 2007 I like your suggestion. I was ready to tear into the instrument cluster to test the switch. Refocusing on the resistor will allow me to troubleshoot away from home. I can leave the multimeter in my car with a stubby flathead and some alligator clips. Since I can drop the glove box by turning those two plastic things on the inside of it, I can expose the air recirculation system much faster than I can remove the air recirculation switch. You also make a good point. I have only attempted to verify the resistance over the blower resistor, but I neglected to verify voltage coming into the resistor. Thanks! Link to comment Share on other sites More sharing options...
crxtacy Posted July 6, 2007 Share Posted July 6, 2007 Link to comment Share on other sites More sharing options...
James Matteu Posted August 4, 2007 Author Share Posted August 4, 2007 I replaced the aforementioned blower resistor (Honda P/N 79330-SV4-003) this morning. No change, the system is still non-functional. The intermittent problem I described earlier does not occur any longer, as of recently, the system never comes on. Link to comment Share on other sites More sharing options...
tcu Posted August 7, 2007 Share Posted August 7, 2007 I replaced the aforementioned blower resistor (Honda P/N 79330-SV4-003) this morning. No change, the system is still non-functional. The intermittent problem I described earlier does not occur any longer, as of recently, the system never comes on. Have You checked and cleaned the connector and lead wires to the motor (yellow/black & Gnd), They can be intermittant, you can monitor the connector with an Led & dropping resistor. Just leave it connected and watch for the light whenever it's supposed to be on. That will leave out the connection to the fan as the problem, then move the test light to the power line input of the reistor. Link to comment Share on other sites More sharing options...
James Matteu Posted August 7, 2007 Author Share Posted August 7, 2007 Checking the voltage from ground to battery is what I have been avoiding since it is labor intensive and tedious. I have a triathlon this weekend (Sprint Distance: 0.4K/16K/5K) so I will probably put it off until the following weekend. I will post the schematic later. I will keep this thread up to date. Link to comment Share on other sites More sharing options...
James Matteu Posted August 7, 2007 Author Share Posted August 7, 2007 Since the motor was operating noticeably slower in the highest setting, I think an LED voltage indicator would be misleading as to what the actual current is in the circuit. I am confident in saying my perception of how bright the LED is versus how bright it should be will be rather arbitrary and trivial. I will stick with my trusty Radio Shack multimeter set to 12 volts DC. 165 Link to comment Share on other sites More sharing options...
James Matteu Posted September 14, 2007 Author Share Posted September 14, 2007 Here is the circuit I am dealing with: Link to comment Share on other sites More sharing options...
James Matteu Posted September 14, 2007 Author Share Posted September 14, 2007 Tonight I did the following: Checked Fuse #8, no breaks Then with the key in (||) position, Checked the resistance between the Black wire on Connection # 612 (C612) and the chassis, no resistance Grounded C612 Blue wire, no Blower Motor response Grounded C612 Blue/Yellow wire, no Blower Motor response Grounded C612 Blue/Black wire, no Blower Motor response Grounded C612 Blue/Red wire, no Blower Motor response As I plugged C612 back in, the Blower Motor turned on (the switch was in position “4”). I disconnected C612 and reconnected it, the Blower Motor turned on again. I disconnected C612 and then reconnected it. The Blower Motor came on and I selected each of the positions (“1” through “4”). Each functioned properly. I put the A/C Switch in the on position and the A/C Condenser Fan came on and the indicator light for the A/C turned on simultaneously. I then disconnected C612, switched the A/C to off, and then reconnected C612. The Blower Motor gave no response. Then with the key in (||) position, C612 connected, and fan switch in position “4” : I disconnected C467 Checked the resistance between the Blue/Red wire on C467 and the chassis, no resistance Checked the voltage between the Blue/Red wire and Yellow/Black wire on C467, with the fan switch in position “4”, 12 Volts Checked the voltage between the Blue/Red wire and Yellow/Black wire on C467, with the fan switch in position “3”, 12 Volts Checked the voltage between the Blue/Red wire and Yellow/Black wire on C467, with the fan switch in position “2”, 12 Volts Checked the voltage between the Blue/Red wire and Yellow/Black wire on C467, with the fan switch in position “1”, 12 Volts Checked the voltage between the Blue/Red wire and Yellow/Black wire on C467, with the fan switch in position “Off”, 0 Volts I waited a few minutes, then returned to the car and checked the voltage again between the Blue/Red wire and Yellow/Black wire on C467, with the fan switch in position “4”, 0 Volts 0 Volts!!!!!!!!!!!!!!! What the %#@&!!!!!!!! Do I need a priest and some holy water?!!! I reconnected C467, no Blower Motor response. I had to stop since it was getting dark. Link to comment Share on other sites More sharing options...
James Matteu Posted September 14, 2007 Author Share Posted September 14, 2007 Oh yeah, I forgot one more thing, HHHHHHHHHHHEEEEEEEEEELLLLLLLLLLLLLLLPPPPPPPPPP!!!!!!!!!!! 248 Link to comment Share on other sites More sharing options...
James Matteu Posted September 14, 2007 Author Share Posted September 14, 2007 When I stepped away from my car, I turned the multimeter off. It is an analog setup and the switch passes over the "150mAmp" selection before shutting down. I did not disconnect my hot connections and inadvertently blew the multimeter's 250mAmp fuse. This is why the volts read zero when I came back. New fuse, then do some more testing. Link to comment Share on other sites More sharing options...
James Matteu Posted September 14, 2007 Author Share Posted September 14, 2007 First I need to buy a new 250mA fuse for the multimeter. The Tests: 1. Check Fuses #17 and #8, again 2. Connect C612-Blu/Red and C612Blk, monitor EMF from C612-Blk to G403-Blk. It should read 12V unless the switch is drawing current. 3. Disconnect C467, then connect C467-Yel/Blk to the Blower Motor. Ground Blower Motor to chassis to bypass all resistors and switches. 4. Key in (Off), unplug Mitsubishi RC-2225. Key in (||), monitor EMF between C405-Blk and Fuse #8, should be 12 V. 5. Recheck EMF across C467-Yel/Blk and C467-Blu/Red for all switch positions, should be 12V 6. Check resistance between C467-Blu/Red and C612-Blu/Red 7. Check resistance between C467-Blu/Red and G403-Blk 8. Remove Blower Motor and inspect internal materials Link to comment Share on other sites More sharing options...
James Matteu Posted September 15, 2007 Author Share Posted September 15, 2007 Results so far: 1. Fuses #17 & #8 are good 3. Out of 7 tries, the motor came on once. It was strong but I shut it down right away to not to cook my jumper wire. 4. 12 V every time. 5. 12V in all positions 7. No resistance Time for lunch. Link to comment Share on other sites More sharing options...
James Matteu Posted September 17, 2007 Author Share Posted September 17, 2007 Yesterday: 2. I skipped this test since I could not get the motor to function in a consistent fashion. Otherwise, the switch test would have been meaningless. 8. I open the bottom cover but could not access the internals. The top part was stuck on, so I skipped this test. I felt I had enough data to attribute the failure to the Blower Motor. Today: I replaced the Blower Motor (Honda P/N 79310-SR3-A01) and the system is now functional. I hope this thread helps the newbies diagnose any electrical problem that comes their way. 285 Link to comment Share on other sites More sharing options...
James Matteu Posted March 8, 2008 Author Share Posted March 8, 2008 As an update to this thread, I have not had any problems with this system since changing the blower motor. Edit: I moved my circuit diagram to Photobucket, Flickr is no good. 426 Link to comment Share on other sites More sharing options...
lceah Posted March 13, 2008 Share Posted March 13, 2008 I've completely missed this. I would have suggested the resistor and you did replace it! good thing it's working now... Link to comment Share on other sites More sharing options...
James Matteu Posted March 13, 2008 Author Share Posted March 13, 2008 good thing it's working now... Absolutely, I would've been in bad shape without the ability to blow hot or cold air from my system. I just hope my thread helps somebody else. I remember there was a guy who had the same problem and was pretty sure his resistor was bad and had just changed the relay (I know, if you read above, that sounds very familiar). I told him to change the motor and sent him to this thread if he didn't believe me, but I don't know what happened to him. Link to comment Share on other sites More sharing options...
ncskates Posted March 14, 2008 Share Posted March 14, 2008 good luck i have no idea how to fix that. Link to comment Share on other sites More sharing options...
James Matteu Posted March 14, 2008 Author Share Posted March 14, 2008 good luck i have no idea how to fix that. I fixed it already. If it ever happens to you, come back here and read on how to fix it. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.