What exactly does a DME relay do, and WHEN DO I KNOW IF THE RELAY NEEDS CHANGING??

[jbripps]

Hi all,

Not much in the archives on this one, unless I didn't search well. Anyway, have seen and heard so much about always having a backup DME relay in case the one in the box goes.

Simple question here, what exactly does the DME do, and when should one know when to check to see if the Relay needs replacing. Where is the DME relay?

I know this is amateur stuff, but I really would like to know (as this is just as important as having a spare tire), so all you Junior Guys pay attention too.

thanks so much,

regards,

[john walker's workshop]

it turns on the fuel pump and the computer that runs the engine. it's next to the computer under your seat. if it's old, replace it as insurance. the engine obviously won't run if it fails.

[Wayne 962]

It's a single point of failure for the entire engine electronics. If the contacts in the relay fail, the engine computer (ignition and Fuel inj) shut off.

Needless to say, they aren't bulletproof, and are a bit faulty sometimes. Best to carry a spare...

-Wayne

[jbripps]

Hey guys,

OK, now I understand what the DME does (thanks so much), but where is the RELAY housed? Is that under the seat too, or is it somewhere in the fusebox?

thanks again.

regards.

[john walker's workshop]

see my 1st post.

[nhromyak]

John W didnt mention it, but sometimes when the relay starts to fail, the engine will miss and have strange problems. Keeping a spare relay on hand is the easiest and best $ thing to try.

Good Luck!