Contour Enthusiasts Group Archives Forums General Troubleshooting Under Hood Light - Always On

Have you ever thought of just keeping it disconnected until you NEED to see your engine in the dark at which time you can just plug the wires together again?

That's what I'm doing now. I don't really plan on spending any money on this repair, was actually just curious as to how it works. I wasn't sure till now. Thanks guys

- Zack

Here are a couple of pictures of the under hood light as requested.

Where abouts is the mercury switch located?

- Zack

Under Hood Light - Bulb Location

Under Hood Light - Wires

Zack showed me Yahoo can be used for my photos. Here are my snapshots:
Underhood light photos

Perhaps being a 95 Mystique LS, the light assembly looks more refined ?

I don't know for sure, but guess that the mercury switch must be encapsulated right at the bulb holder/housing, as visible in your exposed light assembly !

Now, if you allow me to further speculate, the design of Zack's underhood light can be prone to problem: it is horizontal? A vertical mercury switch, assuming it is part of the bulb tubular housing, would provide more "traveling path" for the mercury slug, and thus better ON/OFF switch?

Having said that, is it possible to move your light assy to an angle other than 0 deg., i.e. horizontal? Even a 10 degrees, up or down, may make a different (allowing the slug to make or break the connection)?

Dave

I'm really wondering how you guys could miss the switch. It's not a mercury switch at all, rather a mechanical push type contact switch. Locate the hood bumpers (the little rubber stops on either side of the radiator that attach to the car and adjust the height of the hood when it is open. On the passenger side, there is a plunger type switch that controls the underhood light. Push the plunger down, and the light goes off. Let go and it comes back on. Your switch may be broken. When the dealership broke mine, the light stayed off permanantly, which is the opposite of what you would expect since the plunger is up (in the on position). The dealer replaced it and the light is working as it should again.

The switch is located according to the manual, Engine compartment lamp switch (located at the RH radiator support)


With the headlamp switch in either the PARK or HEADLAMP position, power is provided to the compartment lamp through circuit protection in the instrument panel fuse junction panel.

With the hood (16612) open, the engine compartment lamp switch closes and provides a ground for the compartment lamp.

Ground is provided through Circuit 31 (BK).

Sounds like yours should not be on unless the headlight switch is running at least the side lights? maybe the wire has shorted to ground? but how is power getting to the lamp?

I can tell you that previously (and with other cars) I have had the light on whenver the hood was up, regardless of the lights in PARK or HEADLAMP, but I appreciate the info. I'll look for the switch tonight. Thanks


- Zack

It's about time that I am about face ! I was looking at the wrong location: the hood latch, assuming (incorrectly) that it is similar to a trunk switch!



I don't understand this logic? The headlights don't need to be on for the underhood light to be on! I think the underhood lamp is "Normally ON", meaning the switch is "Normally Closed", supplying the 12V to the lamp: the power comes from the other contact of the switch. If the switch is stuck at 12V, always closed, then the lamp is always on!

I don't know about later ConTique models, '95, '96 models seem to have a common problem of premature battery death. A possible cause is the underhood lamp switch stuck at 12V! This article from Motor Age does offer an explanation:
Inside Look at the Charging System

Excerpt:"If the [parasitic current] draw is excessive, look for things like glove box lamps, interior lamps, or trunk lamps being stuck on...underhood lamps can cause a parasitic draw with the ignition switch off. Most vehicles' underhood lamp switches are turned on when the hood is opened. Although on some vehicles, such as the 1989-'91 Ford Probe, the underhood lamp switch is located on the hood release handle. These vehicles were prone to having the underhood lamp remain on at all times while the hood was completely closed. This condition was caused by the hood release cable binding or becoming misaligned with the switch. When this occurred, the battery would discharge and cause the alternator to fail prematurely"(End of quote)

Lastly, this also means that models without underhood lamp will need an additional switch mounted at the hood bumper. Similar to fog lamps, one would think that rough-in wiring for fog lamps would be there, but they are not!

Dave