Glow Plug Light - Relay Issue - Diesel Place : Chevrolet and GMC Diesel Truck Forums
 
Home Forum Market Place Garage Lounge (0) Tuning Library DTC Tool Register Vendors
Go Back   Diesel Place : Chevrolet and GMC Diesel Truck Forums > GM Diesel Engines > 6.2L Diesel Engine
Register FAQ Forum Rules My Replies My Threads Mark Forums Read Auto EscrowAuto LoansInsurance

DieselPlace.com is the premier Duramax Diesel Forum on the internet. Registered Users do not see the above ads.
Closed Thread
 
LinkBack Thread Tools
Old 05-21-2010, 12:26 AM   #1 (permalink)
84Trav
Diesel Enthusiast
 
Join Date: May 2010
Posts: 7
iTrader Score: 0 reviews

Glow Plug Light - Relay Issue

Hello, I have a 1984 K20 6.2L Diesel . I have been reading extensivly trying to figure out what is wrong and can not seem to pin down exactly what the issue is.

The Glow Plugs do not cycle on when the ignition is turned to the WTS position. That is the light does not come on and the truck does not start if cold.

If warm it will start fine without the glow plugs.

I have new batteries, that crank hard.

I tested the replaced the relay, since it was $20 bucks. Still the First Terminal, that is allways hot draws 12.8V, the second terminal (Red wire, black line) is 12.8V when ignition is turned. The third terminal (blue wire) is 12.8V when the ignition is turned. These are conected with a small resistor, is that normal? The forth terminal (large one) is dead when the ignition is on or off, nothing.....

I have read check the fuses. All the cab fuses are good. Are there fuses in the engine well?

I have read check the grounds, which grounds and were are they located?

The controller is newer, I dont know when, but it looks brand new. Could this be it, how do you test?

If I bypass the relay with jumper cables, the Glow Plug light in the cab turns on and the engine starts in about two crancs and 5 seconds of GP.

Also if the GP light cycles on a few times once the truck is started, this is what it normaly does when everything is working.

Any help would be much apreciated.

Thanks,
Trav

Last edited by 84Trav; 05-21-2010 at 12:41 AM.
Offline  
Quick reply to this message
Sponsored Links
Advertisement
 
Old 05-21-2010, 12:39 AM   #2 (permalink)
Destry
Diesel Technician
 
Destry's Avatar
 
Join Date: Mar 2010
Location: Flint MI
Posts: 112
iTrader Score: 0 reviews

I took an '83 and converted the glow plug system over to the new style timer. I have a schematic posted somewhere here. I think it is a lot better than the old system.
__________________
1995 Chevy 4X4, 1993 6.2, 1993 6.5 manifolds and GM-3 turbo, 6.5 mechanical ip, 6.5 injectors, 26 psi peak on the intake, 3.73, 5 speed manual trans, 5" strait pipe. 28.9 mpg @ 73 mph.

My Big Truck
2000 Volvo VNL610 N14 Redhead Cummins cpl-2592 525 HP 1850 ftlbs torque 18 speed Eaton RTLO20918A Licensed for GVW 130,000 Loaded with crushed cars 80 Yard Rolloff

http://www.youtube.com/watch?v=-DWJpTxgwKk
Offline   Quick reply to this message
Old 05-21-2010, 09:09 AM   #3 (permalink)
4320Diesel
Resident Pinhead
 
4320Diesel's Avatar
 
Join Date: Mar 2009
Location: Grenfell, Saskatchewan
Posts: 6,335
iTrader Score: 0 reviews

Old School Oil Burners (Old SOBs) Member

your problem is the controler. to make the glowplug relay work, the little redwire has 12 volts and the blue wire gets grounded. thats how the controler turns them on and off. the controler is 120 dollars? and it resides on the rear of the driverside head.
__________________
1985 GMC (The Brown Streak) Sierra Classic 1500 4WD With 6.2L V8 Diesel and 4speed NP833 trans with hurst shifter! , 4911 6.5 ip with 6.5 shortie injectors GM-3 turbo. Single plane J code intake from Turbonator (thanks guys!). 3" exhaust and 3" BBQ black stacks! Isspro Pyrometer, Trisco Boost and Engine Oil Temp Gauges.
1995 Dodge 2500 Cummins 12 valve NV4500 4x4 LB club cab autometer boost and pyro BrentBilt fuel plate full forward silencer ring MIA straight pipe AFC totally maxed out
1977 GMC high sierra 6500 2WD with 366V8 and 5+2 speed trans
1968 Mercury (The Tank) M-100 2WD with 300 I-6 and 3 on the tree trans
1971 John Deere 4320 with a 404CID With A Factory Shwitzer 3LD turbocharger Crankin 116 horsepower with over 9700 origininal hours on the engine never rebuilt!
1978 John Deere 8630 with a reman 619 CID Diesel out of a 8650 With A Factory Aireasearch TV-6102 turbocharger Crankin 320 Horsepower and 1700 torque
Quote:
Originally Posted by diaric View Post
your wrong brent, i'll think of a reason later

Quote:
Originally Posted by diaric View Post
brent can't do that, it would look factory, lol

Quote:
Originally Posted by Trios View Post
Brent is right.
Was there any ever doubt?
Offline   Quick reply to this message
Old 05-21-2010, 09:13 AM   #4 (permalink)
Diaric
Administrator
Spam Assassin
The Old Crank
 
Diaric's Avatar
 
Join Date: Jan 2008
Location: Bentley , Alberta
Posts: 23,282
iTrader Score: 2 reviews

Old School Oil Burners (Old SOBs) Member

Alberta Coal Rollers Member

DieselPlace.com Lifetime Premium Member

the 82-84 controller is junk. most don't work out of the box. changing to the newer controller or a manual switch is best. in the 6.2 facts under glowplugs shows how to go manual
__________________
1987 6.2l Jimmy , being restored,4" lift, 35 mudders 1993 W350 5.9 , custom stretched cab, duelly flatdeck
2001 VW TDI Jetta 4 door loaded 2001 VW TDI Golf 2 door swapped engine project
Quote:
Originally Posted by 4320diesel View Post
well to make your pump retarded, you could let it hang out with me for a day
Quote:
Originally Posted by Hawkstrong View Post
Diaric wins thread derailment......
Quote:
Originally Posted by High Sierra 2500 View Post
Yeah Diaric, I gotta say, I'm afraid I'm going to have to give you an official warning on that.
6.2 FACTS AND ANSWERS Click Here
My Restoration Thread Click Here
Alberta Coal Roller Member #2
Offline   Quick reply to this message
Old 05-22-2010, 03:44 PM   #5 (permalink)
Power_Auger
Diesel Technician
 
Power_Auger's Avatar
 
Join Date: Feb 2010
Location: Poulsbo, WA
Posts: 153
iTrader Score: 0 reviews

Old School Oil Burners (Old SOBs) Member

Controller Residence

Quote:
Originally Posted by 4320diesel View Post
your problem is the controler. to make the glowplug relay work, the little redwire has 12 volts and the blue wire gets grounded. thats how the controler turns them on and off. the controler is 120 dollars? and it resides on the rear of the driverside head.
Controllers are JUNK for sure. $140 in my case, for an 84 Controller, lasted 1 day. Mine now resides in the Sh$t Can. These guys here helped me out. My ol tired SOB Starts immediately thanks to the manual GP Switch. My wife now drives it to the store, and won't let me get near it.
__________________
1984 Custom Deluxe 6.2 L - C code - Manual GP Switch

Advocate for GM Glow Plug Controller Waste Management
Offline   Quick reply to this message
Old 05-22-2010, 03:48 PM   #6 (permalink)
4320Diesel
Resident Pinhead
 
4320Diesel's Avatar
 
Join Date: Mar 2009
Location: Grenfell, Saskatchewan
Posts: 6,335
iTrader Score: 0 reviews

Old School Oil Burners (Old SOBs) Member

__________________
1985 GMC (The Brown Streak) Sierra Classic 1500 4WD With 6.2L V8 Diesel and 4speed NP833 trans with hurst shifter! , 4911 6.5 ip with 6.5 shortie injectors GM-3 turbo. Single plane J code intake from Turbonator (thanks guys!). 3" exhaust and 3" BBQ black stacks! Isspro Pyrometer, Trisco Boost and Engine Oil Temp Gauges.
1995 Dodge 2500 Cummins 12 valve NV4500 4x4 LB club cab autometer boost and pyro BrentBilt fuel plate full forward silencer ring MIA straight pipe AFC totally maxed out
1977 GMC high sierra 6500 2WD with 366V8 and 5+2 speed trans
1968 Mercury (The Tank) M-100 2WD with 300 I-6 and 3 on the tree trans
1971 John Deere 4320 with a 404CID With A Factory Shwitzer 3LD turbocharger Crankin 116 horsepower with over 9700 origininal hours on the engine never rebuilt!
1978 John Deere 8630 with a reman 619 CID Diesel out of a 8650 With A Factory Aireasearch TV-6102 turbocharger Crankin 320 Horsepower and 1700 torque
Quote:
Originally Posted by diaric View Post
your wrong brent, i'll think of a reason later

Quote:
Originally Posted by diaric View Post
brent can't do that, it would look factory, lol

Quote:
Originally Posted by Trios View Post
Brent is right.
Was there any ever doubt?
Offline   Quick reply to this message
Old 05-22-2010, 05:18 PM   #7 (permalink)
Power_Auger
Diesel Technician
 
Power_Auger's Avatar
 
Join Date: Feb 2010
Location: Poulsbo, WA
Posts: 153
iTrader Score: 0 reviews

Old School Oil Burners (Old SOBs) Member

Should the Urge Really Strike You,,,,

Quote:
Originally Posted by 84Trav View Post
Hello, I have a 1984 K20 6.2L Diesel,,,,,

The controller is newer, I dont know when, but it looks brand new. Could this be it, how do you test?,,,,,,,,

Any help would be much apreciated.

Thanks,
Trav
1'st WELCOME, A great bunch here!!!! They bent over backwards to get me going. And they DID Get Me Going.

For any UNCONTROLLABLE URGES;

To test the thermal controller, Rear of block (Driver Side) mounted in Block coolant, Round 6 wire plugin.

Disconnect electrical connector from thermal controller.
Measure resistance between controller terminals using high impedance, digital ohmmeter set on 200 ohms scale.
Resistance should be as follows:
Pins 2 to 3 ................0.40---0.75 ohms

Pins 4 to 5 ....................24---30 ohms

Pins 1 to 5 ..................117---143 ohms

Pins 2 to 6 .............Continuity (0) ohms

If resistance values are not as specified, controller is defective.
If resistance values are within specifications, reconnect electrical connector and observe controller operation with ignition key in on position and engine stopped.
If controller cycles more than one time, controller is satisfactory.
If controller cycles only once, check for a short or open in harness.

*************

Then SH$T Can it.

Ron
__________________
1984 Custom Deluxe 6.2 L - C code - Manual GP Switch

Advocate for GM Glow Plug Controller Waste Management
Offline   Quick reply to this message
Old 05-26-2010, 02:36 AM   #8 (permalink)
84Trav
Diesel Enthusiast
 
Join Date: May 2010
Posts: 7
iTrader Score: 0 reviews

Thanks Guys for all the follow up, it was the Controller. Quick fix, runs like a champ now. I hope I can get more than 1 day out of it for $120 bucks.
Offline   Quick reply to this message
Old 05-26-2010, 08:34 AM   #9 (permalink)
sls639
Diesel Master
 
sls639's Avatar
 
Join Date: Dec 2009
Location: Aloha, OR.
Posts: 1,028
iTrader Score: 0 reviews

Quote:
Originally Posted by Power_Auger View Post
1'st WELCOME, A great bunch here!!!! They bent over backwards to get me going. And they DID Get Me Going.

For any UNCONTROLLABLE URGES;

To test the thermal controller, Rear of block (Driver Side) mounted in Block coolant, Round 6 wire plugin.

Disconnect electrical connector from thermal controller.
Measure resistance between controller terminals using high impedance, digital ohmmeter set on 200 ohms scale.
Resistance should be as follows:
Pins 2 to 3 ................0.40---0.75 ohms

Pins 4 to 5 ....................24---30 ohms

Pins 1 to 5 ..................117---143 ohms

Pins 2 to 6 .............Continuity (0) ohms

If resistance values are not as specified, controller is defective.
If resistance values are within specifications, reconnect electrical connector and observe controller operation with ignition key in on position and engine stopped.
If controller cycles more than one time, controller is satisfactory.
If controller cycles only once, check for a short or open in harness.

*************

Then SH$T Can it.

Ron
Sounds like we have a new GP controller expert.
And a new DP addict.
__________________
'84 K1500 Blazer Silverado, 6.2 "red block", Banks turbo returning soon. Modified air intake. Emissions delete. 31.5" ATs.
'93 suburban, 5.7 TBI, fleet (dreamin' of droppin' a 6.2 into her!)
Offline   Quick reply to this message
Sponsored Links
Advertisement
 
Closed Thread

Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Glow plug relay issue with voltage tilt99 6.5L Diesel Engine 7 05-02-2011 04:27 AM
Glow Plug Light Issue TycoRC 6.2L Diesel Engine 9 09-20-2010 11:30 PM
Glow Plug Light Issue koots 6.2L Diesel Engine 27 07-20-2010 12:24 AM
Glow plug relay/controller issue jeffyboy 6.2L Diesel Engine 20 04-05-2010 02:32 PM
Glow plug relay *POPS*...but glow plugs don't light? zeitgeist57 6.2L Diesel Engine 2 06-23-2007 11:37 AM


All times are GMT -4. The time now is 04:45 AM.


Shoutbox provided by vBShout v6.2.1 (Lite) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd. Runs best on HiVelocity Hosting.
© AutoGuide

SEO by vBSEO 3.6.0