Go Back   Honda-Tech > Honda and Acura Model-Specific Technical Forums > Honda Civic (2001 - 2005)
Sign in using an external account
Register Forgot Password?
Search


Welcome to Honda-Tech!
Welcome to Honda-Tech.com.

You are currently viewing our forums as a guest, which gives you limited access to view most discussions and access our other features. By joining our community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join the Honda-Tech community today!


Reply
 
 
 
submit to reddit
 
Thread Tools Search this Thread
Old 01-25-2011, 03:31 PM   #1
It Wasn't Me
Garage is empty, add now
 
Join Date: Sep 2007
Posts: 6,705
iTrader Rating: (0)
Icon6 ► DIY: Radiator Fan Circuit & Fan Switch Circuit Troubleshooting

Before performing any troubleshooting, check the following items:
- Fuses
- Grounds
- Cleanliness and tightness of all connectors

Click the image to open in full size.

Click the image to open in full size. Click the image to open in full size. Click the image to open in full size.




Radiator Fan Circuit Troubleshooting

1. Check the #4 (20amp) fuse under the hood, and the #14 (10amp) fuse under the dash.
Are the fuses okay?
Yes - Go to step 2
No - Replace the fuse(s) and recheck.

2. Remove the radiator fan relay from the fuse box under the hood, and test it.
Is the relay okay?
Yes - Go to step 3
No - Replace the radiator fan relay.

3. Measure the voltage between the #1 terminal of the radiator fan relay 4-pin socket and a body ground.
Is there battery voltage?
Yes - Go to step 4
No - Replace the under-hood fuse/relay box.

4. Using a jumper wire, connect the #1 and #2 terminals of the radiator fan relay 4-pin socket.
Does the radiator fan run?
Yes - Go to step 5
No - Go to step 6

5. Disconnect the jumper wire, and turn the ignition switch ON (II). Check for voltage between the #3 terminal of the radiator fan relay 4-pin socket and a body ground.
Is there battery voltage?
Yes - Go to step 9
No - Check for an open in the wire between the under-hood fuse/relay box and the under-dash fuse/relay box.

6. Disconnect the radiator fan motor 2-pin connector.

7. Check for continuity between the #2 terminal of the radiator fan relay 4-pin socket and the #2 terminal of the radiator fan motor 2-pin connector.
Is there continuity?
Yes - Go to step 8
No - Repair an open in the wire between the under-hood fuse/relay box and the radiator fan motor 2-pin connector terminal #2.

8. Check for continuity between the #1 terminal of the radiator fan motor 2-pin connector and a body ground.
Is there continuity?
Yes - Replace the radiator fan motor.
No - Check for an open in the wire between radiator fan motor 2-pin connector terminal #1 and a body ground. If the wire is okay, check for a poor ground at G201.

9. Reinstall the radiator fan relay.

10. Disconnect the radiator fan switch 2-pin connector. Jump terminals #1 and #2 to see if the fan runs.
Does the radiator fan run?
Yes - Replace the radiator fan switch.
No - Go to step 11

11. Remove the jumper wire, and measure the voltage between the #2 terminal of the radiator fan switch 2-pin connector and a body ground.
Is there battery voltage?
Yes - Check for an open in the wire between radiator fan switch 2-pin connector terminal #1 and body ground. If the wire is okay, check for a poor ground at G101.
No - Repair an open in the wire between the radiator fan switch terminal #2 and the fuse/relay box under the hood.
It Wasn't Me is offline   Reply With Quote
Old 01-25-2011, 03:36 PM   #2
It Wasn't Me
Garage is empty, add now
 
Join Date: Sep 2007
Posts: 6,705
iTrader Rating: (0)
Default Re: ► DIY: Radiator Fan & Fan Switch Circuit Troubleshooting

Radiator Fan Switch Circuit Troubleshooting (Open)

1. Disconnect the radiator fan switch 2-pin connector.

2. Turn the ignition ON (II).

3. Measure voltage between the #2 terminal of the radiator fan switch 2-pin connector and a body ground.
Is there battery voltage?
Yes - Go to step 4
No - Repair an open in the wire between the radiator fan switch 2-pin connector and the fuse/relay box under the hood.

4. Turn the ignition OFF, and check for continuity between the #1 terminal of the radiator fan switch 2-pin connector and a body ground.
Is there continuity?
Yes - Replace the radiator fan switch.
No - Check for an open in the wire between the radiator fan switch 2-pin connector terminal #1 and body ground. If the wire is okay, check for a poor ground at G101.
It Wasn't Me is offline   Reply With Quote
Old 01-25-2011, 03:43 PM   #3
It Wasn't Me
Garage is empty, add now
 
Join Date: Sep 2007
Posts: 6,705
iTrader Rating: (0)
Default Re: ► DIY: Radiator Fan & Fan Switch Circuit Troubleshooting

Radiator Fan Switch Circuit Troubleshooting (Short)

1. Remove the radiator fan relay from the fuse/relay box under the hood.
Is the relay okay?
Yes - Go to step 2
No - Replace the radiator fan relay

2. Remove the radiator fan switch and test it.*
Is the radiator fan switch okay?
Yes - Go to step 3
No - Replace the radiator fan switch.

3. Disconnect the negative cable from the battery.

4. Disconnect ECM / PCM connector B (24-pin) and the under-hood fuse/relay box 14-pin connector.

5. Check for continuity between the #2 terminal of the radiator fan switch 2-pin connector and a body ground.
Is there continuity?
Yes - Repair a short in the wire between the radiator fan switch 2-pin connector terminal #2 and the under-hood fuse/relay box.
No - Replace the under-hood fuse/relay box.


*
Quote:
Testing the Radiator Fan Switch: Link
It Wasn't Me is offline   Reply With Quote
Old 07-05-2012, 04:22 AM   #4
ChrisMaconGa
Honda-Tech Member
Garage is empty, add now
 
Join Date: May 2012
Location: Macon Ga
Posts: 13
iTrader Rating: (0)
Default Re: ► DIY: Radiator Fan & Fan Switch Circuit Troubleshooting

Can I use this also for a 1990 Civic sedan in trouble shooting the fans?
__________________
Chris Brooks - Macon Ga.
ChrisMaconGa is offline   Reply With Quote
Old 07-22-2012, 12:49 PM   #5
THE2003CRV
Trial User
Garage is empty, add now
 
Join Date: Jul 2012
Posts: 8
iTrader Rating: (0)
Default Re: ► DIY: Radiator Fan Circuit & Fan Switch Circuit Troubleshooting

I am trying to find the fan switch 2-pin connector shown but do not see it - - am I looking in the wrong place? Is it close to the fuse block? The relays are ok, and I found the fan motor connector. Honda CRV 2003 4-door
Thanks in advance
THE2003CRV is offline   Reply With Quote
Old 07-22-2012, 02:45 PM   #6
toyomatt84
Sanji
Garage is empty, add now
 
toyomatt84's Avatar
 
Join Date: Apr 2005
Location: ALL BLUE
Posts: 22,162
iTrader Rating: (1)
Send a message via AIM to toyomatt84
Default Re: ► DIY: Radiator Fan Circuit & Fan Switch Circuit Troubleshooting

Quote:
Originally Posted by THE2003CRV View Post
I am trying to find the fan switch 2-pin connector shown but do not see it - - am I looking in the wrong place? Is it close to the fuse block? The relays are ok, and I found the fan motor connector. Honda CRV 2003 4-door
Thanks in advance
You're in the wrong forum.
__________________
*free hugs*


My For Sale Thread
toyomatt84 is offline   Reply With Quote
Old 10-16-2012, 06:31 PM   #7
dc97
Honda-Tech Member
Garage is empty, add now
 
Join Date: Oct 2012
Location: California
Posts: 14
iTrader Rating: (0)
Default Re: ► DIY: Radiator Fan Circuit & Fan Switch Circuit Troubleshooting

5. Disconnect the jumper wire, and turn the ignition switch ON (II). Check for voltage between the #3 terminal of the radiator fan relay 4-pin socket and a body ground.
Is there battery voltage?
Yes - Go to step 9
No - Check for an open in the wire between the under-hood fuse/relay box and the under-dash fuse/relay box.

I have a 97 Integra hence my username..

On my DVOM it shows -0 voltage so meaning theres no voltage going on..

on my schematics it shows a black/yellow wire that goes to the underdash fuse box to fuse #13 (cooling/heater fan relay fuse)

Fuse is good, but i get no power when i hit it with a test light..

Anybody know where the black/yellow wire specifically is by the fuse box (underdash)?

(tired of the bypass that was done by the previous owner and i want my fan running right... running way too rich and not hitting normal temperature + dumping a bunch of fuel)

Thanks.
dc97 is offline   Reply With Quote
Old 10-20-2012, 08:51 AM   #8
Wahabbaluch
Trial User
Garage is empty, add now
 
Join Date: Oct 2012
Posts: 1
iTrader Rating: (0)
Default Re: ► DIY: Radiator Fan Circuit & Fan Switch Circuit Troubleshooting

Excellent trouble shooting tips. After carring out all above checks, finally came to a faulty fan. When it was opened, the fault found in carbon brushes, those were found worn. It is advised that before replacing a faulty fan, its carbon brushes must be checked.
Wahabbaluch is offline   Reply With Quote
Old 04-28-2013, 05:51 PM   #9
jald3rd
Honda-Tech Member
1997 Honda Civic
 
Join Date: Mar 2013
Posts: 3
iTrader Rating: (0)
Default Re: ► DIY: Radiator Fan Circuit & Fan Switch Circuit Troubleshooting

i follow all the steps (check all the fuses and relays, fan working with the jumper, replace the thermostat and fan switch) but the fan still not working when the needle is on H already. I put the jumper back and the fan works and the temperature went down. where else do you think i need to check? thanks
jald3rd is offline   Reply With Quote
Old 12-25-2013, 01:35 PM   #10
Nandasmo
Honda-Tech Member
Garage is empty, add now
 
Nandasmo's Avatar
 
Join Date: Jun 2013
Location: Canada
Posts: 35
iTrader Rating: (0)
Default Re: ► DIY: Radiator Fan Circuit & Fan Switch Circuit Troubleshooting

Thanks for this troubleshooting guide.

Last edited by Nandasmo; 12-27-2013 at 07:06 PM.
Nandasmo is offline   Reply With Quote
 
 
 
submit to reddit
Reply

Tags
block, civic, connector, disconnect, diy, fan, harness, honda, radiator, relay, switch, testing, wires

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump



All times are GMT -8. The time now is 03:37 PM.



2008 Copyright, InternetBrands Inc.
Powered by vBulletin® Version 3.7.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.

Honda and the Honda marquee are registered trademarks of the American Honda Motor Company, Inc. Neither American Honda Motor Company nor its subsidiaries or affiliates shall bear any responsibility for Honda-Tech.com content, comments, or advertising. Honda-Tech.com is not affiliated with American Honda Motor Company in any way. American Honda Motor Company does not sponsor, support, or endorse Honda-Tech.com in any way. Copyright/trademark/sales mark infringements are not intended or implied.
Emails & Contact Details