User Tag List

Reply
 
Thread Tools Rating: Thread Rating: 2 votes, 5.00 average. Display Modes
Old 05-09-2007, 08:00 PM #31
rando's Avatar
rando rando is online now
Senior Member
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
rando rando is online now
Senior Member
rando's Avatar
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
It turns out that soldering the diode DID NOT do further damage to my relay -- I simply made a mental mistake when testing the relay on the bench, post soldering.

More importantly, with the case removed, I can confirm that the diode isn't shunting the kickback (i.e. I can see an arc every time the relay contacts open). Apparently I made a 2nd mental mistake since the diode as installed can't possibly redirect the EMF since it will always be reverse biased. The bypass needs to go to ground. There isn't a ground rail available to this relay, so the bypass diode will have to be installed elsewhere in the circuit.

I'll post an updated solution when I have it -- sorry for any confusion.

Last edited by rando; 05-09-2007 at 09:28 PM.
rando is online now   Reply With QuoteReply With Quote
Old 05-09-2007, 08:04 PM #32
rando's Avatar
rando rando is online now
Senior Member
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
rando rando is online now
Senior Member
rando's Avatar
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
Quote:
Originally posted by TechWrench
Those contacts are, with out a doubt, burnt. I'm hoping the fog light relay holds out until the new relay is available again. I think the original A/C relay lasted 3 years, so I hope we have some time before the next one fries.
I tried to capture a video of the arcing but, as expected, it's too fast to be caught by my digicam.
rando is online now   Reply With QuoteReply With Quote
Old 05-09-2007, 08:44 PM #33
Kmvreter's Avatar
Kmvreter Kmvreter is offline
Senior Member
 
Join Date: Mar 2004
Location: Ontario, Canada
Posts: 3,015
Kmvreter will become famous soon enough
Kmvreter Kmvreter is offline
Senior Member
Kmvreter's Avatar
 
Join Date: Mar 2004
Location: Ontario, Canada
Posts: 3,015
Kmvreter will become famous soon enough
Thanks for the update Rando. I was wondering about the way you wired the diode but wasn't quite sure myself. Now we know.

So I went to poke around under the hood and look in the fuse box. Turns out I don't have to worry about this because the following applies...

Quote:
Originally posted by webshot

The relay that came with the car and is faulty is part number 90987-02022 and is white in color.

It is supposed to be replaced by the newer relay part number 90987-02028 and is grey in color.

This relay is found in the fuse box under the hood marked as "MG CLT". "MG CLT" is short for Magnetic Clutch.
My '04 SR5 already has the grey relay.
Good luck guys.
__________________
__________________

'04 SR5 V6 4x4 Galactic Grey Mica. Delivered 03/17/2004. Link to my mod list in posts 7, 8 & 9 of this thread: http://www.toyota-4runner.org/showthread.php?t=21354
____________
[__/[_[_\____\,_
L---L-L-L--0=*=0
`(o)_---(o)_--)_)`.........
``````````````````````` The battle begins at the end of your driveway... Game On! "Car!"
Kmvreter is offline   Reply With QuoteReply With Quote
Old 05-09-2007, 09:02 PM #34
rando's Avatar
rando rando is online now
Senior Member
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
rando rando is online now
Senior Member
rando's Avatar
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
SOLUTION: MGCLT Relay Mod

The narrative in the following posts describes how I mod'd the magnetic clutch / magnetic clutch sensor circuit to prevent premature failure of the MGCLT relay. In my case, the relay had already failed before I learned of the problem. To test this modification I further destroyed my relay by removing it from its casing. Had the modification been in place earlier, I believe relay failure (and a costly $50+ replacement) could have been avoided.

This modifcation done correctly or not may start your truck on fire, or otherwise cause damage or injury to people, property, or the universe. It worked for me, as described, but I cannot guarantee that it is safe or that it will work for you. By attempting this modification, you agree to proceed at your own risk and accept full liability for your actions and their consequences. The information provided here is for informational purposes only. I do not endorse this modication nor recommend that ANYONE actually perform what is described.


Last edited by rando; 05-09-2007 at 10:53 PM.
rando is online now   Reply With QuoteReply With Quote
Old 05-09-2007, 09:11 PM #35
rando's Avatar
rando rando is online now
Senior Member
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
rando rando is online now
Senior Member
rando's Avatar
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
These are the locations to connect the diode. The diode is hidden underneath the heat shrink. The red sticker indicates the diode anode.

Anode goes to GND - Pin #4 (center pin) of the Heater relay
Cathode (striped side of diode) goes to the load - Pin #3 of MG CLT relay
Attached Images
A/C light flashing??-diode-bypass-jpg 

Last edited by rando; 05-11-2007 at 05:44 AM.
rando is online now   Reply With QuoteReply With Quote
Old 05-09-2007, 09:22 PM #36
rando's Avatar
rando rando is online now
Senior Member
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
rando rando is online now
Senior Member
rando's Avatar
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
Here's what it looks like with the relays installed. Hopefully your MG CLT relay doesn't look like mine!

If you're just reading these last two posts, I've confirmed that this eliminates the arcing inside of the relay. If you have the old style relay and it hasn't failed yet (and you're out of warranty), you can save yourself $50+ and install the bypass for < $1.
Attached Images
A/C light flashing??-diode-bypass-2-jpg 

Last edited by rando; 05-09-2007 at 10:36 PM.
rando is online now   Reply With QuoteReply With Quote
Old 05-09-2007, 09:26 PM #37
greasefingers's Avatar
greasefingers greasefingers is offline
Senior Member
 
Join Date: Aug 2004
Location: Northern VA
Posts: 1,941
greasefingers is on a distinguished road
greasefingers greasefingers is offline
Senior Member
greasefingers's Avatar
 
Join Date: Aug 2004
Location: Northern VA
Posts: 1,941
greasefingers is on a distinguished road
The diode goes across the coil of the relay which one side is ground, so if that pictured diode is across the coil and positioned correctly; then it should work fine to prevent a reverse huge voltage spike when the relay de-energizes.
__________________
2003 4x4 Sport 4runner V8, Scion HU w 4 upgraded speakers, Hella horns, MapLight Mod, de-badged 85 k + miles
1994 Jeep GC with 202,500 miles
1990 Corolla 168,000 miles
1994 Volvo 850 165,000 miles
2003 Camry 12,500 miles
greasefingers is offline   Reply With QuoteReply With Quote
Old 05-09-2007, 09:32 PM #38
rando's Avatar
rando rando is online now
Senior Member
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
rando rando is online now
Senior Member
rando's Avatar
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
Quote:
Originally posted by greasefingers
The diode goes across the coil of the relay which one side is ground, so if that pictured diode is across the coil and positioned correctly; then it should work fine to prevent a reverse huge voltage spike when the relay de-energizes.
No. In this application, the diode is across the load (i.e. the magnetic clutch solenoid), not the relay coil. Without it, the EMF arcs across the relay switch contacts and dissipates into the battery supply circuit. With the diode, the EMF is redirected to ground.
rando is online now   Reply With QuoteReply With Quote
Old 05-09-2007, 09:38 PM #39
greasefingers's Avatar
greasefingers greasefingers is offline
Senior Member
 
Join Date: Aug 2004
Location: Northern VA
Posts: 1,941
greasefingers is on a distinguished road
greasefingers greasefingers is offline
Senior Member
greasefingers's Avatar
 
Join Date: Aug 2004
Location: Northern VA
Posts: 1,941
greasefingers is on a distinguished road
Quote:
Originally posted by rando


More importantly, with the case removed, I can confirm that the diode isn't shunting the kickback (i.e. I can see an arc every time the relay contacts open).
Got ya. If I had read the above more closely then I would have understood.

Nice job Rando!
__________________
2003 4x4 Sport 4runner V8, Scion HU w 4 upgraded speakers, Hella horns, MapLight Mod, de-badged 85 k + miles
1994 Jeep GC with 202,500 miles
1990 Corolla 168,000 miles
1994 Volvo 850 165,000 miles
2003 Camry 12,500 miles
greasefingers is offline   Reply With QuoteReply With Quote
Old 05-09-2007, 09:55 PM #40
rando's Avatar
rando rando is online now
Senior Member
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
rando rando is online now
Senior Member
rando's Avatar
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
Here's the modified circuit. Per the diagram, you could tap D1 at connector IC4 with an in-line tap to get a cleaner install. IC4 is behind the driver kick panel.
Attached Images
A/C light flashing??-circuit-jpg 

Last edited by rando; 05-09-2007 at 10:14 PM.
rando is online now   Reply With QuoteReply With Quote
Old 05-09-2007, 10:34 PM #41
Kmvreter's Avatar
Kmvreter Kmvreter is offline
Senior Member
 
Join Date: Mar 2004
Location: Ontario, Canada
Posts: 3,015
Kmvreter will become famous soon enough
Kmvreter Kmvreter is offline
Senior Member
Kmvreter's Avatar
 
Join Date: Mar 2004
Location: Ontario, Canada
Posts: 3,015
Kmvreter will become famous soon enough
Quote:
Originally posted by rando
you can save yourself $50+ and install the bypass for < $1.
Way to go Rando! I knew you would find the fix for those who need it. Got to love those $1 mods.
Now you need to find a scrap yard and pull a replacement relay for your original. Almost any TOY has that relay.
__________________
__________________

'04 SR5 V6 4x4 Galactic Grey Mica. Delivered 03/17/2004. Link to my mod list in posts 7, 8 & 9 of this thread: http://www.toyota-4runner.org/showthread.php?t=21354
____________
[__/[_[_\____\,_
L---L-L-L--0=*=0
`(o)_---(o)_--)_)`.........
``````````````````````` The battle begins at the end of your driveway... Game On! "Car!"
Kmvreter is offline   Reply With QuoteReply With Quote
Old 05-09-2007, 10:56 PM #42
rando's Avatar
rando rando is online now
Senior Member
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
rando rando is online now
Senior Member
rando's Avatar
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
Quote:
Originally posted by Kmvreter
Way to go Rando! I knew you would find the fix for those who need it. Got to love those $1 mods.
Now you need to find a scrap yard and pull a replacement relay for your original. Almost any TOY has that relay.
I take donations!
rando is online now   Reply With QuoteReply With Quote
Old 05-11-2007, 03:00 AM #43
a77boy a77boy is offline
Member
 
Join Date: Feb 2007
Location: Texas
Posts: 121
a77boy is an unknown quantity at this point
a77boy a77boy is offline
Member
 
Join Date: Feb 2007
Location: Texas
Posts: 121
a77boy is an unknown quantity at this point
Dam Rando you the Freakin' man!! Good job. In the meantime I still need to fart around with my vibrating exhaust which is still driving my crazy at stoplights, Will have to try the diode mod soon.
a77boy is offline   Reply With QuoteReply With Quote
Old 06-26-2007, 11:51 PM #44
gizmopt2002's Avatar
gizmopt2002 gizmopt2002 is offline
Member
 
Join Date: Jul 2006
Location: Chicago, IL
Age: 28
Posts: 821
Real Name: Phil
gizmopt2002 is an unknown quantity at this point
gizmopt2002 gizmopt2002 is offline
Member
gizmopt2002's Avatar
 
Join Date: Jul 2006
Location: Chicago, IL
Age: 28
Posts: 821
Real Name: Phil
gizmopt2002 is an unknown quantity at this point
Question. My A/C wasn't working right, it came out cool instead of cold. I added more refrigerant and now it comes out COLD, but it doesn't work at times, I'm thinking about replacing the relay. Any input?

(BTW, rando, are you an electrician?)
__________________
'95 4Runner V6 4WD 168k SOLD 10/11
'98 Honda Accord LX 4-Cyl 216k
'04 4Runner V6 4WD 157k
Denso Iridium Plugs - Synthetic Fluids - Python Alarm W/Remote start - 265/65/17 REVO's - Silverstars - Ash Tray Mod - WeatherTech Mats
gizmopt2002 is offline   Reply With QuoteReply With Quote
Old 06-27-2007, 12:33 AM #45
rando's Avatar
rando rando is online now
Senior Member
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
rando rando is online now
Senior Member
rando's Avatar
 
Join Date: Feb 2004
Location: Palos Verdes Peninsula, CA
Posts: 1,141
rando is on a distinguished road
If your relay fails, you'll get the flashing A/C light and the compressor will shut off (i.e you just get outside or recirculated air depending on your vent settings). If you push the auto button (or the next time you use your A/C), the system may work again, work for only a short while, or not at all.

No, I'm not an electrician by trade. I do have a CS/EE background though.

Quote:
Originally posted by gizmopt2002
Question. My A/C wasn't working right, it came out cool instead of cold. I added more refrigerant and now it comes out COLD, but it doesn't work at times, I'm thinking about replacing the relay. Any input?

(BTW, rando, are you an electrician?)
rando is online now   Reply With QuoteReply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

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 On

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
A/C Light Blinking on 2003 LTD bluduk15 Problems & Warranty Issues 60 06-18-2019 06:55 PM
D light on dash not lighting up (sometimes): DRC 4th Gen T4Rs 4 10-17-2013 02:09 PM
1st gen brake and charge light flashing?? Leo Ahearn Classic T4Rs 10 05-14-2012 10:09 AM
a/c light burnt out nc211 4th Gen T4Rs 2 01-27-2009 11:22 AM
AC problem: light flashing, no cold air buwen 4th Gen T4Rs 2 03-30-2006 01:31 AM

Powered by vBadvanced CMPS v3.2.2

All times are GMT -4. The time now is 01:37 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.
Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Feedback Buttons provided by Advanced Post Thanks / Like (Lite) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Lite) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
***This site is an unofficial Toyota site, and is not officially endorsed, supported, authorized by or affiliated with Toyota. All company, product, or service names references in this web site are used for identification purposes only and may be trademarks of their respective owners. The Toyota name, marks, designs and logos, as well as Toyota model names, are registered trademarks of Toyota Motor Corporation***Ad Management plugin by RedTyger
 
Copyright © 2019


Garage Plus vBulletin Plugins by Drive Thru Online, Inc.