1997 Ford Explorer - No Power When Engine is Cold

Since you have more than one item failing, and assuming the problems all started at the same time, you need to look for the common denominator, which would be 12vdc and ground. Again since the +12vdc is routed through separate controls and fuses, I would assume the ground to be the common failure. An easy test would be to supply a separate ground by connecting a wire to negative post on the battery and then to the ground point on which ever device is easiest to work on and accessible. Probably the wipers have the most accessible connection and you may even not have to open or disconnect but simply make sure the test ground is attached to the wiper motor frame or mounting bolt. It may also not be a valid test if they use a harness ground. Anyway, I would expect that this does prove that when separate ground is supplied, the device works the same as when the engine has warmed up.

So if it does work now you need to find where that normal ground has a poor connection back to the battery that also would change as the motor warms up and I would believe it to be either the connection on the motor and there may be more than one. They are usually bare braided straps between the motor and the firewall, fender, frame, etc. look for loose connection, loosed bolt, moderate to heavy corrosion at the connections and I even found one that the strap itself had corroded so bad that it did not conduct the ground at all but looked mechanically as if it was connected. If you have a meter, checking Resistance between the points where the ground wires connect may help pinpoint the bad connection but remember that it does change with thermal change so it might also change simply by touch or movement and therefore not a "good" ground. Once the bad one is found, clean all the connection point much the same as you would for a battery post (shinny) and I would use some new wire and bolts

I believe reply #1 by Guest was good advice. You might also , if you haven't looked there yet, check the fuse/ circuit breaker connections at the fuse panel under the dash and some are also under the hood . Sometimes corrosion you can't always see is the cause. All it takes sometimes is to remove the fuse and reinstall it. Its fast and easy. We try the simple things first.

I'm going to take a shot at this without knowing the cold-start circuitry for Fords. Since it only happens when cold, I'm pretty sure that is the common denominator, not a bad ground.

Cars share parts of the power control module's circuitry, and when cold in your case, a temp. sensor switches the firing, fuel flow, and idle rpm to a cold-start setting to warm the car up faster and leaner with a retarded spark, lower fuel and higher rpm. When warm, it returns to normal. I'm guessing that your auxillary circuits are sharing some of the cold-start circuits, and when in cold-start mode, your aux. circuits are out of the equation. You will need to get a wiring diagram that shows you what the common part, such as a relay, is between the aux. system and the cold-start circuits.

I am thinking that in addition to the specific items you mention it would also include all items operated on the "accessory" position of the ignition switch.

My guess is that the ignition switch is not returning to the "on" position immediately after starting. The "start" position is spring loaded to return to "on" and when in "start" it disables the accessory function and restores the accessories when returned to the "on" position. In summary the ignition switch is either dirty or the return spring is broke or weak. You can manually return the switch to "on" after the engine starts.

Hope that this helps.

I have had the same issue with my 1994 Mercy Grand Marque, On very cold days the dielectric grease in the switch hardens and makes it difficult to return to the run position.....

I had this happen on an old 85 Bronco. The ignition switch would not return completely to the run position after starting. It also displayed various warning lights on the dash since the vehicle still recognized the key as being in the start position. Try manually returning the key to the run position and your troubles should be over.