wtf are these and no headlights - The 1947 - Present Chevrolet & GMC Truck Message Board Network

*trkklr77* · 12-30-2006, 08:46 PM

these are on the upper right hand corner of the fire wall. they were wired in with the externaly reg alt harness. i redid my wiring today to mod and move the alt to intr reg and the p-side of the motor.

instead of looping the external reg plug, i eliminated it. i used a small alt harness for a 73+ that had the main power, ext excitor, and the brown wire back to the fire wall, it is charging the batt and powering everything but the headlights.

i dont think they are related but ???????????

corn · 12-30-2006, 08:56 PM

My 69 doesnt have either of them. I cant help you...

BobbyK · 12-30-2006, 10:36 PM

Those are for the TCS(Transmission Controlled Spark)...it's an emmisions thing.
They're relays.
I had a pair in that exact same area of the firewall of my 71 Blazer.
Still had the wiring too...just no TCS solenoid on the carb.

72armyswbtruck · 12-30-2006, 10:37 PM

No Help Here Either

mstone · 12-30-2006, 11:43 PM

They are to engage the A/C compressor when you turn off the engine.
To keep the engine from dieseling. My friends 71 Cheyenne has it. It's an option listed on the option sheet can't remember how they list it though.

72armyswbtruck · 12-30-2006, 11:45 PM

Pics man Pics,
Please

BobbyK · 12-30-2006, 11:47 PM

I thought that A/C relay was located under the dash?

*trkklr77* · 12-31-2006, 03:32 AM

no a/c cab. heater only.

the carb thing ???
i didnt find any stray unidentified connectors, so???????? the harness that hooked to them all seemed to be alt related. do you have any pics of how it connected to the carb or even dia. that lists them???

i also belive i found that the lights are dead due to a bad high beam switch, i could only get power out of one of the 3 prongs .

*trkklr77* · 01-01-2007, 09:02 PM

well the no head lights was cured with a new dimmer switch today.

thanks anyways

**john** · 01-01-2007, 09:14 PM

Quote:

Originally Posted by trkklr77

no a/c cab. heater only.

the carb thing ???
i didnt find any stray unidentified connectors, so???????? the harness that hooked to them all seemed to be alt related. do you have any pics of how it connected to the carb or even dia. that lists them???

The TCS had a solenoid on the carb that controlled the vacuum advance through a signal from trans and a temp switch so you only had vacuum advance in high gear after the engine warmed up .

cdowns · 01-01-2007, 10:00 PM

1relay goes to a tranny control the other to a carb solenoid both are for emissions both are useless both are listed on the 71 factory wire diagram in your 71factory service manual

12-30-2006, 08:46 PM	#1
trkklr77 Account Suspended Join Date: Aug 2006 Location: vacaville ca, because it as far from indy as i can be Posts: 775	wtf are these and no headlights these are on the upper right hand corner of the fire wall. they were wired in with the externaly reg alt harness. i redid my wiring today to mod and move the alt to intr reg and the p-side of the motor. instead of looping the external reg plug, i eliminated it. i used a small alt harness for a 73+ that had the main power, ext excitor, and the brown wire back to the fire wall, it is charging the batt and powering everything but the headlights. i dont think they are related but ??????????? Attached Images

12-30-2006, 08:56 PM	#2
corn Registered User Join Date: Dec 2003 Location: here Posts: 5,789	Re: wtf are these and no headlights My 69 doesnt have either of them. I cant help you...

12-30-2006, 10:36 PM	#3
BobbyK Registered User Join Date: May 2000 Location: Petrolia,Ontario,Canada but working in Port Huron,Mi. Posts: 1,772	Re: wtf are these and no headlights Those are for the TCS(Transmission Controlled Spark)...it's an emmisions thing. They're relays. I had a pair in that exact same area of the firewall of my 71 Blazer. Still had the wiring too...just no TCS solenoid on the carb. __________________ 71 blazer,350SBC,approx.375HP,700R4,factory GM TPI.Dual electric fans,33x12.5x15 ATR on stock suspension. Petrolia,Ontario,Canada but working in Port Huron,MI. See ALL my Blazer pic's HERE

12-30-2006, 10:37 PM	#4
72armyswbtruck Registered User Join Date: Feb 2004 Location: Idaho Posts: 4,033	Re: wtf are these and no headlights No Help Here Either __________________ "Remember, They can Kill You, but they can't eat You, That's against the law!!!!!!!!!"

12-30-2006, 11:43 PM	#5
mstone Registered User Join Date: Mar 2006 Location: Cypres, Texas Posts: 3	Re: wtf are these and no headlights They are to engage the A/C compressor when you turn off the engine. To keep the engine from dieseling. My friends 71 Cheyenne has it. It's an option listed on the option sheet can't remember how they list it though.

12-30-2006, 11:45 PM	#6
72armyswbtruck Registered User Join Date: Feb 2004 Location: Idaho Posts: 4,033	Re: wtf are these and no headlights Pics man Pics, Please __________________ "Remember, They can Kill You, but they can't eat You, That's against the law!!!!!!!!!"

12-30-2006, 11:47 PM	#7
BobbyK Registered User Join Date: May 2000 Location: Petrolia,Ontario,Canada but working in Port Huron,Mi. Posts: 1,772	Re: wtf are these and no headlights I thought that A/C relay was located under the dash? __________________ 71 blazer,350SBC,approx.375HP,700R4,factory GM TPI.Dual electric fans,33x12.5x15 ATR on stock suspension. Petrolia,Ontario,Canada but working in Port Huron,MI. See ALL my Blazer pic's HERE

12-31-2006, 03:32 AM	#8
trkklr77 Account Suspended Join Date: Aug 2006 Location: vacaville ca, because it as far from indy as i can be Posts: 775	Re: wtf are these and no headlights no a/c cab. heater only. the carb thing ??? i didnt find any stray unidentified connectors, so???????? the harness that hooked to them all seemed to be alt related. do you have any pics of how it connected to the carb or even dia. that lists them??? i also belive i found that the lights are dead due to a bad high beam switch, i could only get power out of one of the 3 prongs .

01-01-2007, 09:02 PM	#9
trkklr77 Account Suspended Join Date: Aug 2006 Location: vacaville ca, because it as far from indy as i can be Posts: 775	Re: wtf are these and no headlights well the no head lights was cured with a new dimmer switch today. thanks anyways

01-01-2007, 10:00 PM	#11
cdowns Senior Member Join Date: Jan 2003 Location: daytonabeach Posts: 22,956	Re: wtf are these and no headlights 1relay goes to a tranny control the other to a carb solenoid both are for emissions both are useless both are listed on the 71 factory wire diagram in your 71factory service manual __________________ 71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF DONT BELIEVE EVERYTHING YOU THINK TAKE MY ADVISE;I DON'T USE IT ANYWAY

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