I recently did this mod:

http://users.oco.net/xero/fanmod/

No real complaints, everything works 100%, i love the LEDs, excellent instructions BTW, but my problem is that....if the engine is already running and I turn on the fans it will throw the SES light. Is there any way around this, I would like to have manual control of the fans while sitting in traffic and whatnot without the annoying SES light, do I have anyway around this. The write up says that it should only throw the light if you try and start the car with the fan already on?

 

Wire in the 47 ohm resistors in this diagram and your SES problems will be solved. Sorry, the ultimate fan mod page is not as ultimate as it should be. What it meant to say, is that any time you have the ignition ON and the fan switch on, it will cause a code. Do the reisistors and you shouldn't have any more problem. If all you can find is 1/2 watt ones, they should be ok.

 

good grief i spent forever soldering all that, oh well thats not too much more work. What about the diodes? do I have to have those? my leds operate properly now....but are they needed in case the new resistors interfere with them?

so one led but two in parallel, and on the other fan lead put just one in series?

 

Make it just like the drawing. If you are not having any issues with the LEDs, don't worry about diodes.

 

agreed, that is the same way I wired my switch minus the leds and have had no trouble with the SES light.


However.. I think I might wire up the leds soon sine so far I have left it on low twice and killed my battery


I am thinking of making a plate to go over the ashtray to mount the switch and LEDs as well as for when I ever get an electric cut-out so when you open the ashtray cover all my switches are there. thought that would be nice...

 

what about the diodes? did you use those?

 

I didnt use diodes on my 94. Both LEDs light up when i cut power. (Wired into cig lighter wire) Looks like I have some fancy security system, and the LEDs dont draw any significant power (so no battery drain), so hell, can't be happier

 

If you use switched power for the LEDs (my recommendation), you won't have a problem with the LEDs and shouldn't have to use the diodes at all.

 

I believe its only obd1 cars that have that problem?

 

sorry shoe, one more quick question here, what do you mean by issues? and do the leds come on when the computer turns the fans on? the reason i ask is because i have'nt had any problems with the led's, but tonight i had the a/c off and i turned it on for a sec and the low speed led came on, then i turned it off, and 30sec later the light went off, is it supposed to do that?

if its not, is there anymore details i need to know about the diodes if i need to get them?

thanks for your help man
al

 

You're OK. When the a/c or defrost is turned on, the fans come on. They will stay on for 30 seconds after the a/c or defrost is shut off. Don't think you need the diodes. I am running only LEDs and no fan switch, just to be able to monitor the fans. There are no diodes in my wiring. I am using switched power for the LEDs.

Oh, by issues, I just meant working correctly.

 

OBD1 cars do not require the resistors Shoebox mentioned only the OBD2 cars. The OBD1 cars, however, need to the key to be in the run position (unless constant power is wired to the relay), where as, OBD2 cars are constant +12v and will turn on at any time.

Craig

 

questions regarding OBD-1 wiring

- What does Shoebox mean by switched power for the LEDs? & how would I do this? Will my 95 have constantly lit LEDs w/o this?

- Is it okay to use wire-taps like these instead of cutting/splicing/soldering? (no experience with electrical here )

- What is a good/safe ground?

- Lastly, I assume you disconnect the battery before doing all this? If so, do I run into radio/cd player lock-up issues?

THANKS, Brian

 

Power that is only on with the key ON. You might have them stay on at the wrong time.
Yes
The cigarette lighter has a good ground.
Only if you have a security code stored in your radio, will you need to use it after power is restored.

 

thanks for the information

I guess closest-by switched power source is the radio. On the radio, is it pretty obvious which wire/cable is the power line I need to tap into?

thanks, Brian