what if you turn the dome lights on manually...will it activate? Can you instead wire it to the driver's door light?

 

A few things to keep in mind with your timer:

Don't forget a reverse biased diode on the relay or that 555 willl be very quickly toast from negative going spikes from the relay.

Car power is notoriously dirty and voltage spikes may kill your 555 over time unless you use a 15v transorb on the power rails.

That circuit will draw a constant 10mA or so from your battery...probably not a big deal, but be aware.

 

It won't activate when I turn on the dome lights, Only when the door opens.

I've been looking at the schematic, and I think I can actually tie it into the trunk light. I'm going to experiment with it tomorrow. It looks like the BPM activates the map lights, the foot well lights, and the trunk lights all at the same time. That makes no sense, but still... Maybe I'm looking at the schematic wrong. In any case, I'm just going to take the output from the BPM that turns on the lights when the door is opened and have that activate the timer/relay.

Hmmm... that means the relay will also be activated when I exit the car. I need to think about this, but I've had too many gin and tonics tonight (Bombay Sapphire ). I'll give this some more thought tomorrow when I can think straight.

 

Well, it's not as easy as I was hoping. I tied it into the wire that goes to the dome light in the coupe. The wire is there in the center console, is just doesn't go anywhere because my car is a convertible. I wasn't thinking about how often the lights come on. They come on when I open the door to enter the car. They come on when I turn off the key. They come on when I open the door to get out of the car... I don't think it would do any harm for the pump to run that much, but I'd prefer for it only to run for a few seconds before I start the car. So... I'm going to run a wire up to the driver's door and activate my timer with the door unlock signal. Unfortunately, the door unlock signal is a positive voltage and to activate my time I need a negative input. I'm going to have to wire the door unlock signal to a relay which I will then use to send 0v to the timer module.

And I bet no one is actually paying attention anymore, but that's OK. I kinda type this stuff to help me work through issues.

 

OK... another problem. Does anyone know where to find switched 12v in the center console?

 

NEVER MIND!!! DUH! Cigarette lighter!

 

you say something

 

Does anyone know the best way to get my door unlock signal out of the door and into the center console? That connector in the door hinge won't work because it's a solid connection. There's no way to pass a wire through it.

 

Easiest way AFAIK (and not that easy) is to go through the door wiring boot to the fender (like the remote top module...hope you saved the plastic needle ), then up into the brake booster compartment using one of the existing rubber grommets. Once in the brake booster compartment, you will see a big rubber boot going into the floor of the compartment. Pull up that grommet on the base of the boot, and thread your wire through using a stiff piece of solid wire (12 AWG is good). Then pull your wire through the foam below the comparment using the 12 AWG wire again. It will emerge under the dash. From there you can route it to the console.

 

Thanks for the tip, but I figured it out. The "cannon plug", as we called the Marines, in the door hinge has three empty pins. I figured out that I could push a wire through the pin hole and get it into the car from the door. I had to use a mirror to make sure the wire was going through the same hole on the plug and on the socket, and it was tough finding the wire once it was in the car, but I got it through.

 

That is pretty clever! That could provide an alternative way to wire the remote top module without going under the hood.

 

Trust me... It was much easier to get the wire up under the hood. Going through the plug is obviously do-able, but finding where it went up under the dash took a while.

 

To wrap this up, I installed a PAC TR-7 which is triggered by the door unlock pulse. When I hit the unlock button on the remote it triggers a relay which turns on the fuel pump for 8 seconds to prime the fuel line. by the time I sit down and crank it up it starts instantly! This isn't the ideal solution. I should have just changed the fuel pump. But I'm cheap and I can't see changing out a $500 fuel pump over a stupid check valve. When the fuel pump finally craps out on me, which it will do eventually, I'll change it out then and remove my primer. But until then, the system that I rigged up will keep me from embarrassing myself around the Mercs, Beemers, and Lexi.

 

Sam,

In case, as you're anticipating, this rears its ugly head again, what do you think of the following as a solution which could prevent having to remove the pump? (I'm assuming the pump itself will still pump.)

As I understand your diagnosis, the root of the problem is that:
- The valve thingy in with the fuel pump which is supposed to hold pressure in the fuel line at shutdown is not doing so, and ...
- Inserting a check valve into the line as a fix for that sometimes results in TOO much pressure in the line, at least for a period of time. (We want, what, 30 PSI or so there, right? I'll use the number 30 in what follows.)

So: picture a mod to the fuel line that always allows flow toward the engine, but acts as ... not a check valve, blocking all flow ... but a relief valve which blocks back-flow unless pressure exceeds 30 PSI, then bleeds off any pressure above that. Wouldn't that replace the function of the failed or failing valve located in there with the fuel pump?

I know squat about what fuel plumbing components might be out there to do this, but if nothing simpler exists, it could be realized by a check valve in parallel with a relief valve.

This is sort of a hydraulics-based, rather than an electrically-based, approach to the problem. I was due for one of those.

 

That would be ideal, but I wasn't able to find anything like that. Trust me... I looked.

 

I had to do a double-take to make sure I wasn't hallucinating the author of this statement

 

Tell me about it. I felt much the same way as I was writing. it.