01 F350 glow plug relay ?

[Dave]

just went to test the relay key off the always on side read 12.3 volts the other side read 0 like its supposed to when you turn the key on the ignition controlled side reads 9 to 10 volts Is the relay good or bad

[Dave]

just wonder because it barely wants to start below 18 degrees and its gonna get colder than that here over the next few days

[ford4442003]

When the controller is pulled in both the large lugs should show the same voltage to ground.

[ford4442003]

Sorry I misread it is marginal both sides of the ralay should read the same when key is on there may be a small difference but it should not be a volt difference and yes when key is off there should be voltage on 1 side you could turn key on and with a ampmeter check for a amperage draw between both large terminals when solenoid is pulled in.

[Dave]

would love to but the way it looks my meter will only read up to 10 amps in that mode

[ford4442003]

Yes, you are probley correct alot of household meters amly go up to 10 amps then take your volt meter and while relay is pulled in check voltage across the 2 large lugs if the internal connection is good in the relay you should read no or very low voltage less than 1 volt but only while relay is energized.