After some exploration, I’ve figured out how to modify the foglamp circuit for a 2001 Explorer so that the foglamps stay on with the high beams. This mod is actually much easier, IMHO, than for the earlier models.
First, I located the relay box. It’s mounted to the same plate that holds the bottom of the airbox. I got into it, and here’s what I found:
1. There are sockets for a total of six relays, two large (the size of a conventional Bosch relay) and four smaller relays, in a 1 2 1 2 configuration. The six sockets were arranged like this, with socket 1 being toward the front of the vehicle:
1
2 3
4
5 6
On my Explorer, socket 1 was empty from the factory.
2. The small type relays in sockets 2 and 3 control the foglamps. Why two relays? One to turn on the foglamps when the parking lamps go on, the second to turn off the foglamps when the high beams come on.
3. By checking the wiring on the back of the relay sockets, I came to the conclusion that relay 2 as shown above turned off the foglamps. Why? It was wired so that power flowed when the relay was _NOT_ energized.
4. The small relays, Ford part number F57B-14B192-AA, SPST relays. There are 5 pins on the relay, laid out as follows:
------- 3
------- 5
| | |
| | |
2 4 1
Pins 3 and 5 are .25" wide; pins 1, 2, and 4 are smaller, about .187".
The corresponding sockets are not numbered at all that I can detect.
5. Relay 2 is wired so that power flows from pin 3 to pin 4 when the relay is not energized. Only when the relay is energized is the power cut off. Power goes from pin 4 of relay 2 to the control circuit side, pin 1, of relay 3. In other words, run a jumper from the furthest away wide socket to the center narrow socket of relay 2, and the foglamps don't go off when the high beams come on.
6. To make the foglamps stay on when the high beams come on, I removed relay 2 and ran a jumper wire from pin 3 to pin 4. Just as simple as that.
7. I made a jumper from 16 ga. wire with a male spade connector on each end. For the wide connector I used 3M from Wal-Mart. For the narrow connector I used Radio Shack #64-3134. I didn't measure, but the assembled length of the whole thing was about 2" to 2.25". Jumpered pin 3 to pin 4 and it works like a charm.
The whole procedure took about 20 minutes to actually do, but would have been 5 minutes or so shorter, less the following: When wrestling with the airbox, (a) It came loose suddenly, (b) My head banged into the hood, (c) The drop light fell, breaking the bulb, and (d) I had to find a new bulb for the drop light.
This worked on my 2001. I suspect it will work on any 1999 to 2001 Explorer where the foglamps already come on with the parking lights, and it may be useful for the 2002s and later.
BTW, the wiring to the fog lamps is badly undersized and the pins on the bulbs are badly undersized also. My bulbs are the, I think, 9145s, that have an H-1 bulb grafted onto an adapter. No way I'm going to go over wattage with this dinky wiring.
--
FWIW; AFAIK; IMHO; YMMV; yadda, yadda, yadda.
Regards, Ed Mann mailto:edlmann@earthlink.net
First, I located the relay box. It’s mounted to the same plate that holds the bottom of the airbox. I got into it, and here’s what I found:
1. There are sockets for a total of six relays, two large (the size of a conventional Bosch relay) and four smaller relays, in a 1 2 1 2 configuration. The six sockets were arranged like this, with socket 1 being toward the front of the vehicle:
1
2 3
4
5 6
On my Explorer, socket 1 was empty from the factory.
2. The small type relays in sockets 2 and 3 control the foglamps. Why two relays? One to turn on the foglamps when the parking lamps go on, the second to turn off the foglamps when the high beams come on.
3. By checking the wiring on the back of the relay sockets, I came to the conclusion that relay 2 as shown above turned off the foglamps. Why? It was wired so that power flowed when the relay was _NOT_ energized.
4. The small relays, Ford part number F57B-14B192-AA, SPST relays. There are 5 pins on the relay, laid out as follows:
------- 3
------- 5
| | |
| | |
2 4 1
Pins 3 and 5 are .25" wide; pins 1, 2, and 4 are smaller, about .187".
The corresponding sockets are not numbered at all that I can detect.
5. Relay 2 is wired so that power flows from pin 3 to pin 4 when the relay is not energized. Only when the relay is energized is the power cut off. Power goes from pin 4 of relay 2 to the control circuit side, pin 1, of relay 3. In other words, run a jumper from the furthest away wide socket to the center narrow socket of relay 2, and the foglamps don't go off when the high beams come on.
6. To make the foglamps stay on when the high beams come on, I removed relay 2 and ran a jumper wire from pin 3 to pin 4. Just as simple as that.
7. I made a jumper from 16 ga. wire with a male spade connector on each end. For the wide connector I used 3M from Wal-Mart. For the narrow connector I used Radio Shack #64-3134. I didn't measure, but the assembled length of the whole thing was about 2" to 2.25". Jumpered pin 3 to pin 4 and it works like a charm.
The whole procedure took about 20 minutes to actually do, but would have been 5 minutes or so shorter, less the following: When wrestling with the airbox, (a) It came loose suddenly, (b) My head banged into the hood, (c) The drop light fell, breaking the bulb, and (d) I had to find a new bulb for the drop light.
This worked on my 2001. I suspect it will work on any 1999 to 2001 Explorer where the foglamps already come on with the parking lights, and it may be useful for the 2002s and later.
BTW, the wiring to the fog lamps is badly undersized and the pins on the bulbs are badly undersized also. My bulbs are the, I think, 9145s, that have an H-1 bulb grafted onto an adapter. No way I'm going to go over wattage with this dinky wiring.
--
FWIW; AFAIK; IMHO; YMMV; yadda, yadda, yadda.
Regards, Ed Mann mailto:edlmann@earthlink.net
