Adding Remote Locking

[Gary Lewis]

Am I reading the Horn Relay (for speed control trucks) correctly in that it is ground triggered?

So the DB wire (notated 1) at the bottom right of the relay image that goes to the speed control switch is open but goes to ground when the horn button on the steering wheel is pressed?

Yes, the DB wire goes to ground when the horn button is pushed - on a truck with speed control.

Odd that Circuit #1 is the horn. I would have thought when they started numbering they would have started with something like ignition.

[kramttocs]

Yes, the DB wire goes to ground when the horn button is pushed - on a truck with speed control.

Odd that Circuit #1 is the horn. I would have thought when they started numbering they would have started with something like ignition.

Very true, didn't even think about that

Thanks for that confirmation - that is great news for those with speed control. On the keyless entry module I am installing and most I have found for comparison, the horn output (for Panic mode and lock/unlock confirmation) is a ground output. So no 'user supplied' relay is needed and the DB wire for the factory relay can be hooked into instead.

 

[Gary Lewis]

Very true, didn't even think about that

Thanks for that confirmation - that is great news for those with speed control. On the keyless entry module I am installing and most I have found for comparison, the horn output (for Panic mode and lock/unlock confirmation) is a ground output. So no 'user supplied' relay is needed and the DB wire for the factory relay can be hooked into instead.

That certainly is good news.

So, when the dust settles you'll do a how-to on installing keyless entry?

Reminds me, I think I'll go scan in that section from the '96 EVTM. Might be able to find one of those in a salvage and graft it on.

[kramttocs]

That certainly is good news.

So, when the dust settles you'll do a how-to on installing keyless entry?

Reminds me, I think I'll go scan in that section from the '96 EVTM. Might be able to find one of those in a salvage and graft it on.

That's what I am hoping. I know I've taken over this thread but I assume the stuff I am running into will be pretty generic for all systems. Once I get everything finalized I'll consolidate it and add photos. The 535T Window module is a bit out there so if I cover it, I'll do it in another thread or my build thread to avoid any confusion in this one.

[Gary Lewis]

That's what I am hoping. I know I've taken over this thread but I assume the stuff I am running into will be pretty generic for all systems. Once I get everything finalized I'll consolidate it and add photos. The 535T Window module is a bit out there so if I cover it, I'll do it in another thread or my build thread to avoid any confusion in this one.

Yes, I think it is pretty much all generic to other systems. In fact, take a look at how the '96 keyless entry system controls the horn - upper right below.

And, we have the '96 KES on the website now: Documentation/Electrical/EVTM/1996 EVTM/Keyless Entry.

[kramttocs]

Yes, I think it is pretty much all generic to other systems. In fact, take a look at how the '96 keyless entry system controls the horn - upper right below.

And, we have the '96 KES on the website now: Documentation/Electrical/EVTM/1996 EVTM/Keyless Entry.

Thanks a lot for adding that 96 doc.

Good news and bad news on the factory horn relay.

It works but not well enough. I guess the 200mA output isn't enough to fully energize that style of relay. So instead of honking it just kind of does a very quiet and weak grunt.

I twist-wired in a ground triggered/ground out relay with the output still going to the DB of the factory relay and ground trigger being the 200mA from the Viper module to test with and it works great. Honks the same as if you use the steering wheel button.

At least with any system that only output 200mA, it appears a newer style relay is needed.

Could be:

1. Inline (before the factory relay like in my testing)

2. In place of the factory relay

3. In the engine bay with a ground triggered/12v out relay directly feeding the hot side of the horn

3 is what I was originally going to go with and looks like I am back to that

[Gary Lewis]

Thanks a lot for adding that 96 doc.

Good news and bad news on the factory horn relay.

It works but not well enough. I guess the 200mA output isn't enough to fully energize that style of relay. So instead of honking it just kind of does a very quiet and weak grunt.

I twist-wired in a ground triggered/ground out relay with the output still going to the DB of the factory relay and ground trigger being the 200mA from the Viper module to test with and it works great. Honks the same as if you use the steering wheel button.

At least with any system that only output 200mA, it appears a newer style relay is needed.

Could be:

1. Inline (before the factory relay like in my testing)

2. In place of the factory relay

3. In the engine bay with a ground triggered/12v out relay directly feeding the hot side of the horn

3 is what I was originally going to go with and looks like I am back to that

I think I'd be inclined to go with Door #2. One less thing to go wrong.

But, I'd test it first. There's some real trickery going on with the resistors in the horn pad. So I'd put a Bosch relay in the factory relay's place and check. Pretty sure it'll work. And it is by your right knee.

[kramttocs]

I think I'd be inclined to go with Door #2. One less thing to go wrong.

But, I'd test it first. There's some real trickery going on with the resistors in the horn pad. So I'd put a Bosch relay in the factory relay's place and check. Pretty sure it'll work. And it is by your right knee.

I keep going back and forth It would definitely be one less thing to go wrong.

Out of curiosity I measured the draw of the relay by hooking one lead to the test wire that was jammed in the female spade terminal (for DB) of the connector and then pushed onto the relay. The other lead I grounded. Horn went off (strong sound) and the multimeter showed a .15 draw.

I would have expected the 200mA to handle it but guess not.

[Gary Lewis]

I keep going back and forth It would definitely be one less thing to go wrong.

Out of curiosity I measured the draw of the relay by hooking one lead to the test wire that was jammed in the female spade terminal (for DB) of the connector and then pushed onto the relay. The other lead I grounded. Horn went off (strong sound) and the multimeter showed a .15 draw.

I would have expected the 200mA to handle it but guess not.

It is apparently a voltage thing then. Most solid state systems will have a .7v drop across them, and perhaps battery voltage less .7v isn't quite enough to pull that relay in.

Do you have another of those relays? Check to see what it takes.

And back to the doors, since you are big on leaving the truck such that it could be put back stock, I guess having another relay wouldn't be a bad thing. But, since you have already added a lead to the ground side of the stock relay, why not put the to-be relay in the cab next to the factory relay? That way the RKE system can be removed, along with the extra relay w/o having to fish wire from under the hood.

[kramttocs]

It is apparently a voltage thing then. Most solid state systems will have a .7v drop across them, and perhaps battery voltage less .7v isn't quite enough to pull that relay in.

Do you have another of those relays? Check to see what it takes.

And back to the doors, since you are big on leaving the truck such that it could be put back stock, I guess having another relay wouldn't be a bad thing. But, since you have already added a lead to the ground side of the stock relay, why not put the to-be relay in the cab next to the factory relay? That way the RKE system can be removed, along with the extra relay w/o having to fish wire from under the hood.

I didn't even think about voltage drop.

If I was going about this differently I would hands down look into replacing the factory relay with a bosch style. Even securing a bosch relay to the same bolt as the factory relay and wiring it inline would still be clean.

And at least it gives others some options. I don't have another relay like that in my shop but next time I get to my parents (parts trucks) or jy I'll pull one and test it.

But unfortunately, like you stated, neither of those really fit with my standard...approach(?). Whatever the word would be.

So I made a factory looking jumper to go between where the DB wire connects to the yellow wire (for dual horns) up by the left hand turn signal

I have a plan for how the final relay will be installed and wires routed but for right now I have just hooked up one of the fused relays and have it hanging out on the drivers side platform.

I think that leaves the Ground When Armed /Starter Kill as the only thing left before a guide can be put together.