Centech Gremlins to Kill

[SevenT]

Centech Harness Gremlins

First problem:

The orange female spade at the wiper switch is applied to the wiper switch for power at 950 (Power In for Wiper) in accordance with Centech. Moved my radio and Dakota Digital to the pigtail off of the Accessory fuse. My windshield frame is grounded since it is on a fiberglass tub. Wash function works on the switch. When I try to use the wipers, the voltage drops to 7.4 volts (according to the Dakota Digital face) and cannot make the wipers move. I will need to move the radio and Dakota Digital to another key-on 12V source. Where can I find that source?

Second problem:

I found the column hazard switch to be causing the intermittent flash on the left front. That is resolved. However, when the flasher is activated, all turn signals and marker lights flash. This get worse with the turn signals. Left turn works perfect. Right turn makes all turn signals and markers blink. The left side lights are not as bright, but still on.

Third problem:

The air horns will blow if I ground the relay. When the one-wire column is hooked up, nothing to the horn on the yellow wire. Kinda stumped on this one as well.

This is disappointing, I want this to work and cannot seem to make it do so. Any help is appreciated.

v/r,

SevenT

 

[chuckyb]

1. You could run a wire from the accessory post on the ignition switch for keyed power.
2. Did you actually replace the hazard switch? Even with my hazard switch operational, I needed to replace it in order to eliminate turn signal gremlins. Jim from Centech suggested this and he nailed it in five minutes after I fought turn signals for two weeks.

 

[tpatton75]

Check for ground at steering wheel and run test power to wiper motor to see if it works my harness had a ground wire for wiper motor

 

[68Broncoz]

First issue
Are you sure your battery is good? Can you measure the voltage at the battery when you turn the wiper? There is no way for the voltage to go to 7 volts without blowing a fuse.
Second issue I would check grounds including running a temp ground wire just to be sure.

 

[SevenT]

All,

Thanks for the inputs. I will answer in turn.

68 Broncoz:
My battery is new. I have not measured voltage at the battery while working the wiper switch. The Dakota Digital (DD) is only seeing 7.4 volts because of the drain with the wiper switch on and the radio connected to the accessory feed wire. The DD and the radio are moving to the center post on the ignition tomorrow. Thanks Chuckyb.

TPatton75:
I grounded the steering column under the dash. I neglected to attach that ground in the wiper motor harness. That will get done tomorrow.

Chuckyb:
I have a new hazard switch coming, mine is 50 years old. Hope this helps the blinker/flasher issue.

As for my horn. How do I get ground from the horn button to the air horn relay via the horn wire (Yellow) at the column and at the horn in the Centech harness?

BTW, Centech makes a great harness, their Tech Support is cryptic via email and seems to be less helpful as time goes on. Just a note for those looking at this harness.

v/r,

SevenT

 

[omureebe]

I had a few issues that turned out to be the Centech installer's fault. That would be me. But calling the Tech line got everything figured out. Good luck - sounds like you're woking through it, albeit painfully.

 

[DirtDonk]

As for my horn. How do I get ground from the horn button to the air horn relay via the horn wire (Yellow) at the column and at the horn in the Centech harness?

Which steering column and horn contact (turn signal switch) setup are you using? The original style from '70?
If so you have two contacts for the horn. One was originally power "IN' to the switch, the other was power "OUT" to the horn. Neither one is automatically a ground, as they are just completing a circuit. This circuit can be either one, depending on how you wire it.
Centech uses a horn relay in their harness independent of your separate air horn relay. Normally you can wire it either the old Ford way, or the new Centech way. The wires will do whatever you tell them to do

Will you be using both the air horns and the stock horns? If only one horn, you might not even need the new air horn relay and can utilize the one in the Centech harness and just use the power OUT to power your compressor. Should be robust enough as-is.

In lieu of that however, your "ground" will actually be one of the wires marked for the horn. How many column wires for the horn are there, and what do the column wires say on them? One says "horn coil" perhaps? And the other two?
Or are there only two horn wires total in the new harness now? I seem to remember someone saying that it has changed in this regard, but not sure. Maybe 904Bronco can chime in since, other than his most recent two re-wires, he's done several Centech harness re-wires.

Either way you wire it though, you can use the stock horn button wires for either 12v positive, or ground. Either can be used to trigger a relay.
Just depends on what the wires say on them, and how you wire it.

I thought we'd talked about that relay already somewhere, but don't see it. Is the relay with the air horns using the standard numbering system of 30, 85, 86 and 87 for it's terminals? Or is it something different?

Paul

 

[SevenT]

Paul and others,

I bought a Summit Racing 30 inch floor shift tilt column (SUM-771713B-NK). It has a GM comb connector that is wired to the Centech harness connector. I bought a steering wheel and horn button to fit this column (SUM-772712 and SUM-772802). It has only one wire from the button.

I do not have a stock horn, only the air horns. The relay that came with the horns has 12V on 86 and 30. Horn is on 85 and the compressor is on 87. If ground at pin 85, the horns blow.

I moved my Dakota Digital and radio to the back of the ignition switch. Grounded the wire at the wiper motor to the windshield frame and now my wipers work. Success.

Got my new hazard switch in and still have the same problem as before. When the flashers are on all turn signals and marker lights blink. Left turn is OK, right turn makes the markers and left rear (dim) blink.

I wish I could get this straight, I want to drive this thing.

Thanks for all the help.

v/r,

Mike

 

[DirtDonk]

Horn is on 85 and the compressor is on 87.

You mean the horn button is on #85, correct?
If so, and it's hooked up correctly, it should honk as long as the horn button is connected properly.
If not, then the only thing left is that the column is not grounding with the button. As an experiment, ground the horn contact under the steering wheel with a jumper wire.
If that works, then follow the money. Temporarily jumper the steering shaft inside the column to ground. This is probably easiest out at the lower end near the firewall. If the horn button honks the horn now, you just need to figure out how to get the shaft grounded permanently. Usually the stock shafts are good to go with just a jumper strap around the rag joint. But if you have dual u-joints/yokes like most aftermarket shafts, it might work the same way. Usually they don't need to be jumpered/bypassed though. There is usually enough metal-to-metal contact for them to work as-is.

So find out where the ground stops. Grounding the housing is usually not good enough since the horn button typically grounds through the shaft to the chassis ground system.
Find out why yours is not grounded. Assuming the horn button works as expected with the use of a jumper wire.
If not, it's on to Plan-B!

Paul

 

[DirtDonk]

Got my new hazard switch in and still have the same problem as before. When the flashers are on all turn signals and marker lights blink. Left turn is OK, right turn makes the markers and left rear (dim) blink.

Still not sure what's going on here. Usually an issue like this is a bad ground, but this does not sound like one (then again, when it doesn't sound like a bad ground it usually is!).
It's acting mostly correct, but mostly doesn't cut it.
What do you mean by the left side is OK? It should not do anything to interrupt the hazards whether the key is ON or OFF.

When the flashers are on, all four corners flash and the dash indicators flash along. So we're good so far.
When you hit the brakes they will all stop flashing. Is this how yours works too?
However, your turn signal is NOT going to work on either side when the flashers are engaged. Flip the switch and nothing happens. Lights stay flashing.
But dimming is not an option I would not think.

Your turn signal and hazard switch are separate then? Still using a stock one in the dash? Or is the Centech one different from stock? I forget.
I thought the GM switches had theirs integrated into the turn signal switch like the later Fords did. Doesn't sound like it in this case though.

Paul