Mechanics

AUTOMOBILE

1999 Mercury Marquis • V8 • 130,000 miles

Engine wont turn over not even a click sound, however all chimes headlights blowers power locks work digital dash remains dark, #2 fuse under hood ( covers starter relay, ignition switch, appears intact) how do I use a volt meter to check this fuse?
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Vince danagher
February 19, 2011.



If the dash doesn't light up, you may have an ignition switch problem. To test the starter circuit, find the relay on the inner fender near the battery. One of the red positive battery cables bolts to it. There is a red / blue wire plugged onto the small terminal on top. Unplug that wire, then run a jumper wire from the battery positive post to that terminal. Be sure the car is in "park". If the starter cranks the engine, that circuit is good.

You CAN use a voltmeter to test a bunch of fuses quickly, but to just check one fuse, it's much faster to just pull it out and look at it.

Caradiodoc


Caradiodoc
Feb 19, 2011.
Thank for your reply, is the ignition switch some how responsable for the digital dash not lighting up, anyways re the ignition switch, when key is inserted chimes come on, so in spite of chimes comming on ignition switch may still be faulty? Thanks in advance


Tiny
Vince danagher
Feb 19, 2011.
Yup, there could be three totally independent circuits in the switch. The circuit that supplies the starter switch contact could be the same one that supplies the dash. They use different circuits to spread the load out to reduce overheating one set of contacts, and so when one system fails, not everything goes dead. The engine will still run so you can drive safely off the road when the instrument cluster fails. If the radio and power window circuits stops working, you'll still know how fast you're going, etc. If they just used a single circuit in the switch, everything would go dead at once and you would have to search in a lot more places to find the problem.


Caradiodoc
Feb 19, 2011.
So, I guess if there is no fuse to check for a faulty starter switch I need a new starter switch plus keys, I have a chart that shows # 2 fuse 30 amps, servicing starter relay, generater, ignition switch feed to central junction boxes fuses 15 and 18 . Is there anything to check here? Mind you im only amassing this info waiting for a break in the weather as the car is in the driveway and its too cold right now for me to do much thank you


Tiny
Vince danagher
Feb 20, 2011.
Let's eliminate the easy stuff first. Reread the procedure for jumping the starter relay by the battery. That will verify the starter, relay, and the high-current wiring is good.


Caradiodoc
Feb 20, 2011.
Ok your right ill get back to you after I jump the starter


Tiny
Vince danagher
Feb 20, 2011.
Ok, I installed brand new battery today and attempted to jump start on my car red battery cable and red /blue wire is mounted on side of fuse box I unhooked these and tried jumping starter, all I got was radio playing from inside car plus some clicking from underneath the engine, I went from positive battery terminal to bolt I unhooked the battery cable and red and blue wire from.


Tiny
Vince danagher
Feb 20, 2011.
The radio should not be playing. To be sure you're jumping it right, use this picture. 1. Unplug the red wire from the relay. 2. Connect a jumper wire between the battery positive post and small relay stud as shown.

A simpler alternative method is to just touch a screwdriver to that small stud and the larger stud, (number 3) at the same time.


Caradiodoc
Feb 20, 2011.
Hate to tell you this but my car doesnt have that relay just a underhood fusebox in front of battery, the battery positive cable is connected to the end of the fuse box, let me know if I owe you more money as this is taking longer than I thought


Tiny
Vince danagher
Feb 21, 2011.
Darn the bad luck. This is a picture of a '94 model. The part shown used to be used as the solenoid that switched the very high current on and off to the starter. In later years Ford finally started using a starter with a built-in solenoid like Chrysler and GM use, but they kept on using that part as just the starter relay that only switched a very small current. I thought you might still have that on a '99 model but apparently you now must have the more common relay in the fuse box. I'm not sure what style relay you have but I have a bunch of them here that are identical to some common Chrysler relays. Remove your starter relay, then either pop the cover off, reinstall it that way, then squeeze the contact to see if the starter cranks the engine, or you can use a piece of wire or stretched out paper clip to connect the terminals in the socket. Use terminals 87 and 30 or the two with arrows pointing to them. Holler back with the results.

Caradiodoc


Caradiodoc
Feb 21, 2011.
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