Time Delay

-
rmchrgr

rmchrgr

Skate And Destroy
Joined
Apr 15, 2008
Messages
3,964
Reaction score
1,115
Location
Stamford, CT
What exactly does the accessory time delay feature do? This is for a '71 Duster.

Reason I ask is because I am trying to strip out all the unnecessary circuits in my dash harness but am finding a bunch of stuff is wired into the time delay feature - marker lights, beam selector switch etc.

I got rid of the map lights, ignition lamp, glove box and ash tray lamp. There is no radio or heater. I am installing aftermarket gauges so the printed circuit board will be gone. There is a trunk light too but I have not done anything with that yet.

Can I get away with cutting out the time delay on some of these individual circuits or does it need to stay for some specific reason?

Not sure if an aftermarket harness has this feature but if it did, how would it be accomplished?

Thanks for any input.

- Greg
 
The time delay avoids the transients that happen when the ignition key is switched from crank, to run. Starters have high current and inductance, the alternator is also trying it's best to fill the dip in voltage due to crank, when cranking stops, load drops at the same time as inductive kick comes out, a rocky time for several milliseconds. The delay lets voltage stabilize. Some things are built to handle, others go poof.
 
Huh. Didn't really think of it like that, thanks.

At the same time though, I have changed A LOT of stuff so I'm not sure it's totally necessary in my case.

  • Battery in the trunk with remote starter solenoid
  • Mini starter solenoid is run off a Bosch relay
  • Denso alternator with internal regulator tied to a busbar, power from switched 12v, CD solenoid in trunk to work with cutoff switch
  • MSD 6 which bypasses the ballast resistor, power from busbar and switched 12v
  • No heater
  • No radio
  • No wipers
  • No washer pump
  • Headlights on relays
  • Ammeter is bypassed
It's really a bare-bones set up. Whadya think? Still needed or...?
 
The problem is more with electronic items, things like phone chargers, dash cams, gps .... devices that may power from 12V receptacle. Most things like that instructions recommend, plugging in after a start. If none of that stuff, not much worry except MSD, it needs peak currents because it boosts voltage for HV capacitor charge. It needs a well bypassed low impedance feed. It might need bulk capacitor, like used on audio power amps, installed near MSD. Best to have alternator feed battery, then tap power from there. Bus at alternator will be full of AC ripple, with frequency increasing with RPM. Feeding the MSD with ripple, may shorten life of parts in it. They are not very reliable on a good day. Just my opinion, if you want to be better informed use a scope, measure ripple and see if that exceeds ripple specs of caps used in MSD...
 
Sorry Kit but I'm not so sure the Time Delay has anything to do with what you are describing. I could be wrong, no disrespect meant.

In any event, I believe it's for the A01 light package, which my car has. These are convenience lights - ignition, map and courtesy lights. The ignition lamp stays on for a bit after the door is closed, maybe the dome light too.

There are three things that appear to be related to the Time Delay circuit on my '71 wiring diagram - delay relay connector, acc. lights time delay connection and acc. delay relay. These each have multiple connections feeding several different outlets.

These ignition lamp never worked on my car so I guess I have no physical reference for it.

What I was curious about is why some other things were tied into the circuit, like the dimmer switch. I'm looking at a diagram now, it's not really conclusive but I can't see how taking this circuit out would cause any harm. Again, no ignition lamp. All the other stuff related too that harness is gone as well.
 
I assumed ACC is the accessory feed, a delay after key on, reduces transients and is commonly used on modern cars. I am no expert on 71 mopars, I have not tinkered with one of those, so I could be totally wrong.

I read your post again and seems like the power is fed from battery not alternator, so that is a good thing. I need to refrain from posting on my phone, it is very hard to read a post, and reply, my memory is failing me short term.
 
How can I tell if my 72 Dart swinger came with the time delay relay? Is it a designated "A01" build option? This is my plate. Would the "A01" be on this plate? I can't find a delay relay behind my dash as I'm trouble shooting my dome lamp issue.

0801161908_HDR.jpg
 
96bansheepilot said:
How can I tell if my 72 Dart swinger came with the time delay relay? Is it a designated "A01" build option? This is my plate. Would the "A01" be on this plate? I can't find a delay relay behind my dash as I'm trouble shooting my dome lamp issue.

View attachment 1715289033
Click to expand...
I believe that info would only be on the build sheet.
 
The time delay is for the key -in lamp and seat belt warning lamp "Feel free" to remove it LOL
 
All A01 cars came with them and it is simply a thermal relay that starts heating up and closes it contact as soon as a door is opened and then slowly cools and allows the lamp at the ignition switch to turn on until it cools such that it opens back up turning the lamp off. The longer the door stays open the hotter it gets and longer it stays energized or closed. They were used right up to 2002 and are readily available.
 
96bansheepilot said:
How can I tell if my 72 Dart swinger came with the time delay relay? Is it a designated "A01" build option? This is my plate. Would the "A01" be on this plate? I can't find a delay relay behind my dash as I'm trouble shooting my dome lamp issue.

View attachment 1715289033
Click to expand...

You would see the A01 option listed on the tag. It is not there. If it is on your build sheet, compare and be sure all the VIN matches. Not every option got on the tag but A01 usually did.

This is what it looks like and what it controls. On my 69 the lamp mounts on flat plate sandwiched between the ingintion switch and dash frame, but you should get the idea.

83273BFB-23E3-4023-99D3-F4654D33D8A5.jpeg


8648D305-3249-439E-AA45-80A25E8B5847.jpeg


282E007C-FD0E-4CBB-A9DC-A6824DB004FF.jpeg
 
Last edited:
rmchrgr said:
What exactly does the accessory time delay feature do? This is for a '71 Duster.

Reason I ask is because I am trying to strip out all the unnecessary circuits in my dash harness but am finding a bunch of stuff is wired into the time delay feature - marker lights, beam selector switch etc.

I got rid of the map lights, ignition lamp, glove box and ash tray lamp. There is no radio or heater. I am installing aftermarket gauges so the printed circuit board will be gone. There is a trunk light too but I have not done anything with that yet.

Can I get away with cutting out the time delay on some of these individual circuits or does it need to stay for some specific reason?

Not sure if an aftermarket harness has this feature but if it did, how would it be accomplished?

Thanks for any input.

- Greg
Click to expand...

Kill it.

You say you already removed the ignition lamp and that is all it controls. Sorry but just re-read you initial post.

I like it personally and the map and rest the stuff you pulled. But to each there own. Change them lamps to LED’s and basically no draw on the battery and lights that may help!
 
You must log in or register to reply here.
-

Back
Top