Glow Plug and Battery Check lamps does not come on....schematics please.

**Ry_Tower** · June 15th, 2011 05:15 PM

Originally Posted by miked

got some info from pocuk.com. hindi ko na nakopya yung exact link.....my truck have 2 cylindrical thingy near the battery similar to what i saw at pocuk.

from the looks of the wiring in-vehicle, it may look like a series....what i'm thinking about is this: if 1 glow plug burns out, you can't use the others. then this type of wiring is not reliable. there must always be a plan B. the rest should always function. and if you want the rest to function, then parallel wiring......plus the glow plugs have one hot wire feeding them distributed to each glow plug via the plate. the return to ground is the glow plug body threaded to the cylinder head. i dunno but i doubt the info on the internet that says series wired.

bad thing i don't have my tester with me.

yes dapat parallel yan kaya yung supply ng power dapat sa lahat para mahihirapan ka lang sa starting kung 3 na busted GP. Kung 2 pa lang kaya pa yan umaandar ng 1 click pero medyo matagal na redundo.

**jick.cejoco** · June 15th, 2011 05:36 PM

Originally Posted by miked

got some info from pocuk.com. hindi ko na nakopya yung exact link.....my truck have 2 cylindrical thingy near the battery similar to what i saw at pocuk.

from the looks of the wiring in-vehicle, it may look like a series....what i'm thinking about is this: if 1 glow plug burns out, you can't use the others. then this type of wiring is not reliable. there must always be a plan B. the rest should always function. and if you want the rest to function, then parallel wiring......plus the glow plugs have one hot wire feeding them distributed to each glow plug via the plate. the return to ground is the glow plug body threaded to the cylinder head. i dunno but i doubt the info on the internet that says series wired.

bad thing i don't have my tester with me.

this must be something new to me. since the '70's, all of the automotive diesels that use glow plugs have been connected in parallel. that, the body of the glow plug serves as the ground path and the screw on the top, being the positive connection using an aluminum strip or stainless steel buss bar. this must be new

**miked** · June 15th, 2011 06:26 PM

^no sir. nothing new. some of the usual sorts of misunderstanding the wiring as one fellow posted series wired. that's why i stated my reasons on the second paragraph that it must be parallel wired. well, you know that sometimes looking at the schematics will tell a parallel then when someone look at it in-vehicle it may look like a series. we all know that the glow plug wiring haven't changed that much. what i need ASAP is the schematic diagram.PLEASE

.....why wouldn't the batt checklamp light up the same time with the glow plug checklamp?

**adamsapple** · June 15th, 2011 06:43 PM

Kung ok ang glowplug/ fuse, baka relay or timer ecu ang problema niyan.nangyari na sakin yan may problema timer ecu & walang akong time maghanap kung emergency pwede kang gumamit ng wire atleast guage 10 tapos connect 1 end sa + ng battery connect mo other end sa glow plug plate makikita mo yan sa taas ng glowplug lahat naka connect dyan positive polarity yan para magamit ma start mo..ako pinagawa ko sa electrician nag lagay ng bosh relay 40amperes tapos switch mas maganda pa kaysa original na connection dahil 5 seconds lang pwede ng start di tulad ng original connection may timer atleast mga 20 seconds bago uminit mag beep na pwede na start.di pa ako nakahanap ng original parts kaya eto gamit ok naman. iniwan ko kasi van sa gf ko paalis na ako balik abroad kaya walang time maghanap ng parts pero ok naman.matagal ng gamit ok naman.parang sa mga pampasadang jeep na diesel ganyan din ang connection sa glowplug.at the same time pwede rin anti carnap yan kapag gumamit ka ng switch naka tago or di halata para sa glowplug di ma start kapag di mo alam switch. Hindi pwedeng mag post ng diagram dito kaya try ko Pm sayo diagram flowchart ng toyota atleast makakuha ka idea

**jick.cejoco** · June 15th, 2011 07:25 PM

Originally Posted by miked

^no sir. nothing new. some of the usual sorts of misunderstanding the wiring as one fellow posted series wired. that's why i stated my reasons on the second paragraph that it must be parallel wired. well, you know that sometimes looking at the schematics will tell a parallel then when someone look at it in-vehicle it may look like a series. we all know that the glow plug wiring haven't changed that much. what i need ASAP is the schematic diagram.PLEASE

.....why wouldn't the batt checklamp light up the same time with the glow plug checklamp?

yes you are right in a way there is a dropping resistor in series with the glow plugs. i am looking at a 1985 mitsubishi truck 2.3 diesel. there are two power sources, one from relay glow plug relay l comes straight from the battery to terminal 30 to terminal 87 a on the relay to the 4 glow plugs direct. from glow plug relay 2, power to the dropping resistor then distributed to the parallel connected glow plugs comes from terminal 30. both glow plug relay 1 and 2 are activated by the glow control unit. relay 1 works as a fast glow if the coolant temperature is 86 degrees fahrenheit or lower, relay 2 with the dropping resistor works if the coolant temperature is above 86 degrees fahrenheit. from this control unit, a circuit controls the charge warning indicator, hence, the battery warning light malfunction. the common denominator for your symptoms is the glow control unit assuming your truck uses the same wiring as the u.s. version of the above mentioned truck

**miked** · June 15th, 2011 07:50 PM

Originally Posted by jick.cejoco

yes you are right in a way there is a dropping resistor in series with the glow plugs. i am looking at a 1985 mitsubishi truck 2.3 diesel. there are two power sources, one from relay glow plug relay l comes straight from the battery to terminal 30 to terminal 87 a on the relay to the 4 glow plugs direct. from glow plug relay 2, power to the dropping resistor then distributed to the parallel connected glow plugs comes from terminal 30. both glow plug relay 1 and 2 are activated by the glow control unit. relay 1 works as a fast glow if the coolant temperature is 86 degrees fahrenheit or lower, relay 2 with the dropping resistor works if the coolant temperature is above 86 degrees fahrenheit. from this control unit, a circuit controls the charge warning indicator, hence, the battery warning light malfunction. the common denominator for your symptoms is the glow control unit assuming your truck uses the same wiring as the u.s. version of the above mentioned truck

that's a 4d55 motor, right? most probably they have the same wiring. anyway i jotted down your info. that's a big help. though am not sure with regards to the temperature-related wiring....i'll inform you all next week...will do this weekend given a nice weather as i don't have a closed garage.

**jick.cejoco** · June 15th, 2011 08:10 PM

Originally Posted by miked

that's a 4d55 motor, right? most probably they have the same wiring. anyway i jotted down your info. that's a big help. though am not sure with regards to the temperature-related wiring....i'll inform you all next week...will do this weekend given a nice weather as i don't have a closed garage.

i have this information from alldata information system, i apologize i can not attach the diagram. maybe, if it is not resolved yet, i'll just email you the diagram from a scanned hardprint.

**miked** · June 16th, 2011 07:56 PM

Originally Posted by jick.cejoco

i have this information from alldata information system, i apologize i can not attach the diagram. maybe, if it is not resolved yet, i'll just email you the diagram from a scanned hardprint.

actually, that's a good place to start from....i downloaded some pics (in pdf files) from the internet. well, just enough to guide me through the spaghetti wiring. thanks.

**miked** · June 21st, 2011 06:51 PM

Last friday night, Voltmeter says 12.33V. Since lower than 12.6V, I readily assumed the alternator is not charging. Did some test the following morning and here are the results:

Battery voltage (engine off): 12.43V
Glow plug resistance (Kitahara PM-75): 0.5 ohms (bet. GP top terminal and body) while the other three reads 0.7-0.8 ohms.

Then connected the voltmeter to measure the pre-glow voltage on the GPs, it read 10.6V and what surprised me upon switching to ON is that both the battery charge and glow lamps illuminated.

GP voltage during cranking: somewhere 5.6 -8.++ Volts (readings change too fast) then 0V a few seconds later.....Then the battery voltage while idling went back to 13.88-14.00 Volts. I don't really know what it's up to but I think it's an oxidized connection somewhere.

as of present, it starts ok. lamps ok. didn't bother to go down further on the wirings because i may "knock-out" some connections without my knowing.

FYI