My van is a 1997 e150 i have a headlight problem.When i turn on the hi beams the dash lights and parking lights go out i believe its the headlight relay but i can not locate the relay.Does any body know where the headlight relay is?

 

There is no headlamp relay.

Many Ford owners make, and intall their own relay harness for the headlamps. Or, there are aftermarket kits available. Ford also had a recall on some vehicles, like Mustang.

The problem you've discribed is caused by "voltage drop" i.e. bad ground, or very likely corrosion in the headlamp switch, mult-function switch, and/or connector(s).

Perform close visual inspections, and voltage drop tests to determine where is the problem.

It is possible to remove the multi-function switch, dissasemble, and clean the contacts. However, depending on how bad it is, and whether, or not, the contacts are burnt this switch may need to be replaced. If you do use the same switch make sure to smear dielectric grease on all contacts, and terminal connections before assembly.

Please note too, that my advice is at best an educated guess. I do not have the van available to make a diagnosis with conviction. Do research on test procedures, study wiring diagrams, and use divide and conquer methods to find faults in electrical systems.

Do let us all know what you find. This is a rather commen problem with Ford headlamps. Feel free to ask anymore questions.

Cheers.