manual fan switch causes mil on low?

[white96six]

hey there I rigged up a manual fan switch to just turn on the low fan and it causes the service engine soon lite to come on. It was my understandin that the low fan wont trigger the light. what can I do to make it not turn the lite on? thanks [img]graemlins/burnout.gif[/img]

[Wicked 3800 V6]

This isn't advanced tech!

It's a matter of resistance -- some folks have experimented with putting resistors in line (not for the LED) to fool the computer. I haven't -- whatever, if I get a MIL, it goes away quick enough. And the switch is too nice to let go.
-Rob

[Dominic]

Actually its not resistance, its a diode issue. Adding small diodes in specific places to control the current flow solves the problem.

However, yeah, running either fan without the PCM knowing will turn on the SES. However, it will go off in a few days so dont worry [img]smile.gif[/img]

[white96six]

ok thanks i guess i should wire it to make the high fans come on since i will get the mill either way right? thanks.

[Wicked 3800 V6]

Nah, go ahead and use the low when you need the low, and high when you need the high. No big deal.
-Rob

[Magnus]

moving to general.