'97 expy, acc delay of windows, how to include the radio along with the windows.

[IMINYOURCHAIR]

Hi, as the title states, I want to have my radio power delayed as the windows are when the key is removed. Looking at the service book, I should be able to run a wire from the acc delay relay (or splice into it at the harness near the door) and run that wire to the blk/pnk wire (the one that tells the radio to turn on) and have it work that way, the only issue I worry about is that back feeding into something else, so, I may put a 2.5 amp fuse inline before I commit to safe guard the circuit.

has this been done before? also, Is the behavior of mine not normal? ex: when I go from run to off, the windows still work and the int lights do not come on and the radio goes off. any other car I've had the radio and windows still work and the interior lights come on when the key is removed.

 

[stamp11127]

You should check the amp load of the radio before tying into the circuit. I'm sure it pulls more than 2.5 amp.

Why do you want the radio to work with the key in the off position?

 

[IMINYOURCHAIR]

Good of you to mention checking the amp load, I will verify that the turn on wire doesn't draw more than half an amp before I try anything. although I don't expect it to as the unit simply uses that as a signal to turn on, and draws it's real current from another wire. like how the radio tells the amp to turn on via the blue wire from the head unit.

Why do I want to do this? I have an aftermarket radio and when I switch from run to acc it reboots it which takes a few seconds. Nine times out of ten I make that switch after I park at work or home and want to finish whatever song is playing. making this connection should keep it alive when I turn the key from run to acc.

 

[stamp11127]

One thing that comes to mind is the response time of the current relay to the trigger signal. If it isn't fast enough the radio may still see power off when switching to the acc position.

See the link below for a solid state relay:
Automotive Time-Delay Relay

You can use the same logic as in the headlight delay circuits to accomplish what you are looking for.

 

[IMINYOURCHAIR]

Decided to check that, from what I observed, the GEM keeps the relay closed as soon as the key is turned on and does not open it even slightly from run to off to acc. even quickly switching form the two doesn't open it until the door is open. We shall see tomorrow of it works. Like i said above, I will test it before cutting and terminating the final connections. I like to solder and heatshrink insulate the connections, especially in any automotive work.

 

[IMINYOURCHAIR]

Okay, I managed to find the switched feed wire from the door panel. it is a rather thick wire so the minimal draw from the ign switch sense wire should be fine. the problem I have now is getting to that wire on the inside of the truck. From as far as I got I need to lower the GEM to even see the wire I need. I'll take some more time with it tomorrow. ran out of light today from fixing the right rear door glass.

 

[IMINYOURCHAIR]

Okay, I guess I can say I have figured out how to do it,

remove the left front kick panel, there are two or three harness connections there. the lower connection with the blu black wire is what you want.

on the radio side you want to disconnect the acc wire (red on aftermarket systems) connect the radio side of this wire to the blu black wire on that harness and with the door closed turn the key to acc or on then back off. the radio will stay on, open the door and it will turn off.

I thought I needed to remove the gem to get at the harness but it turns out it runs elsewhere. the good news there is I got to check for water and it's all just dust from the air.

 

[IMINYOURCHAIR]

Alright, to summarize, The idea I had worked quite well, and allowed me to tackle another idea i had.

For teh final install I ended up running an 18 or 20 awg (forgot to check) after measuring the current from the sense wire. it was so low the meter didn't even register. so, I added the adapter from my xm radio to it, less than an amp.

I connected the wire first to the blu/blk switched wire feed to the left front door. this wire is switched from the acc delay relay and gives me the function I want. it also has enough capacity to take an extra half amp load from an xm radio.

from there I added an inline fuse of 5 amps (smallest I had) to protect the circuit should it short to ground. then I routed the wire up and over the steering and brake/accel pedals and up to the radio. As i mentioned, I had to disconnect the factory acc wire due to back feed issues. I hardwired a 5v adapter to power my xm radio to have it power off/on with the radio.

I soldered all the connections and secured the wires where I could. so it should last the life of the truck.

 

[bedrck46]

see attached prints Would they had helped you?

 

[IMINYOURCHAIR]

If it said where that connector was in the first place, yes. FWIW Pin 7 is what I connected to.

If all of this is on that dvd you suggested I order then I will be golden. it cost me $9.50.

 

[bedrck46]

I have 4 of those manuals covering 1996-2008 those are only the tip of the ice burg so to speak some of the years I can just copy to the computer but your year I have to print then copy to the computer Sometimes you just have to do a lot of browsing to find what you want and when you compare the price to Clymer or the others it a hell of a deal when you get it make yourself a back-up copy or two You also will have to down load it to your computer just follow the directions and if you have any question let me know