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PonyGuy
10-25-2011, 12:59 AM
I haven't been active here on MM.net, but over at the CVN site, a solution to the problematic LCM has come about; I apologize if this is already common knowledge here at MM.net, but if it's new to everyone, it's overdue.

Once the LCM has the crappy relay replaced (I think FastBlackMerc does this repair) I rewired my GMQ's headlight circuit to power the headlights directly from the battery through a big honkin' 30-40 amp relay and 12 gauge wire. A member at CVN built a few of these relay and wiring harness assemblies for me and some of his other friends.
This solution helps out a couple of ways:
1.) The headlights run at full battery power, and do a much better job of lighting the road... especially with SilverStar Ultra headlamp bulbs.
2.) This mod takes the heavy 10+ amp headlamp load off the puny little (very marginal) relay in the LCM, and makes the LCM last a lot longer. Since this modification also eliminates the sudden loss of headlight function, it's also a significantly helpful safety issue.

I have no idea how Ford managed to convince anyone at NHTSA that this was not a genuine safety issue, but someone should hang for this. The idea that someone could drive any distance using the Flash-to-Pass feature as the sole headlight source is ludicrous. The engineer who signed off on the design of this LCM arrangement should go back to designing flashlights and crystal radios for Cub Scouts.

fastblackmerc
10-25-2011, 01:56 AM
I haven't been active here on MM.net, but over at the CVN site, a solution to the problematic LCM has come about; I apologize if this is already common knowledge here at MM.net, but if it's new to everyone, it's overdue.

Once the LCM has the crappy relay replaced (I think FastBlackMerc does this repair) I rewired my GMQ's headlight circuit to power the headlights directly from the battery through a big honkin' 30-40 amp relay and 12 gauge wire. A member at CVN built a few of these relay and wiring harness assemblies for me and some of his other friends.
This solution helps out a couple of ways:
1.) The headlights run at full battery power, and do a much better job of lighting the road... especially with SilverStar Ultra headlamp bulbs.
2.) This mod takes the heavy 10+ amp headlamp load off the puny little (very marginal) relay in the LCM, and makes the LCM last a lot longer. Since this modification also eliminates the sudden loss of headlight function, it's also a significantly helpful safety issue.

I have no idea how Ford managed to convince anyone at NHTSA that this was not a genuine safety issue, but someone should hang for this. The idea that someone could drive any distance using the Flash-to-Pass feature as the sole headlight source is ludicrous. The engineer who signed off on the design of this LCM arrangement should go back to designing flashlights and crystal radios for Cub Scouts.

I did the wiring upgrade but I also installed HIDs..... much better lighting.

burt ragio
10-25-2011, 05:36 AM
Do you have a link on the wire relay upgrade ?

ctrlraven
10-25-2011, 05:57 AM
I did the wiring upgrade but I also installed HIDs..... much better lighting.

Do you think it's smart to do the wiring upgrade even if someone is already running HIDs?

PonyGuy
10-25-2011, 10:24 PM
Do you think it's smart to do the wiring upgrade even if someone is already running HIDs?

I don't know what the HID circuits look like, but if their circuit passes more than about an amp through any of the LCM relay contacts, I'd do the external relay upgrade. It can't hurt, it can only help.

Frankly, when I have a little "spare time" (WTF is that?) I'm going to study the entire LCM output circuitry to see if more load current can be shifted away from the LCM relay contacts. Ford's wiring is marginally sufficient at the very best, and downright scary at many other times. The de-contenting and ˘heaping-out all across the vehicle simply disgusts me.

fastblackmerc
10-26-2011, 02:32 AM
Do you think it's smart to do the wiring upgrade even if someone is already running HIDs?
No.... the wiring upgrade was to get more power to the headlights. If you running HIDs your headlights are 100% better than the stock setup.

IMHO the headlight relay inside the LCM is the weak link in the lighting system. If you've replaced it with an external 30/40 amp relay your good..... if not send me your LCM... if your headlights haven't gone out, they WILL!