2004 Bew Tsb for hard starts
first, a quick comment on this excellent write up, it would be nice to know what pin 57 does?
completing this TSB would be made easier by not disturbing the splice of the pin 43 side to the 2 sensors wires, I would snap the black wire on the 2 wire side,
and since I'd like to wire in a toggle switch to be able to reverse the tsb to its original wiring, I would leave a 2" of wire out of the splice, if you opt not to go with a switch I'd just trim it as it exits the splice.
then I would install the repair wire and connect it to the loose black wire going to the sensor, this way you are only working with a single splice.
Anyway, I stumbled across this post while searching for wiring/schematic of the GP relay, I have an 04 Jetta BEW, my problem is with long cranking ONLY in extremely cold weather, NO problem in wet or dry, only when engine is cold and temp is below -10C, or colder.
I still have the steelies, VW dealer gave me the brush off when I took in the letter I received from VW Canada.I was told it is OK as long as it eventually starts then you are ok....and now the recall has expired...
I believe my current problem can be fixed if the Glow plugs remain lit longer, and in order to fool the ECU with infinite reading from the ECT,
this apparently causes the ECU to keep the voltage on to plugs(via relay) for the maximum setting of 25 seconds or so, as stated on many threads I read on here.
So I built me a switch assembly, where I can flick a switch on, causing an open to the ECU from the ECT, then proceed with the normal starting procedure, this also lights up an LED to remind the me I am in the FOOL mode and to go back to normal once the engine starts and stabilize.
And while at it, I added a couple of other goodies, incorporated into the same assembly.
switch 1, controls the Fool mode on/off and turns the LED to the left.(as a reminder)
switch 2, is for a digital volt meter that will be installed in the blank space next to the driver's seat warmer switch.
switch 2 when up, it displays the car 12V supply from a switched source, the VM also provides the charging system health, and the condition of the battery during the GP cycle, cranking cycle as well.
switch 2 when down, measures the voltage supplied to the glow plug,(plug #1, is tapped as a source), and this position also doubles as Off position of the voltmeter display, as it may become a distraction at night, due to the bright blue display.
the 4 LEDs, to the right of this switch act as a visual indicators of voltage being supplied to plugs, tapping point is at GP harness.
(does anyone know if the source of the power/contact to the plugs is bridged for all 4, or each uses a separate relay contact ?
I bench tested it and it works as intended, but will not know for certain till installed and the weather falls below -10C, but it should not hurt, I hope !
Sorry guys, I am not sure how to attach a photo, maybe I do not have the permission yet, help if you can, maybe I can email it to a member who can. thx/ SAM
Switch 1 is DPDT
Switch 2 is SPDT
grounds for the LED use limiting resistors, the 12v on the left has a 470 ohm, the glow plugs Leds use 390 ohm.
a picture is worth a thousand words, I wish I knew how to post one.
first, a quick comment on this excellent write up, it would be nice to know what pin 57 does?
completing this TSB would be made easier by not disturbing the splice of the pin 43 side to the 2 sensors wires, I would snap the black wire on the 2 wire side,
and since I'd like to wire in a toggle switch to be able to reverse the tsb to its original wiring, I would leave a 2" of wire out of the splice, if you opt not to go with a switch I'd just trim it as it exits the splice.
then I would install the repair wire and connect it to the loose black wire going to the sensor, this way you are only working with a single splice.
Anyway, I stumbled across this post while searching for wiring/schematic of the GP relay, I have an 04 Jetta BEW, my problem is with long cranking ONLY in extremely cold weather, NO problem in wet or dry, only when engine is cold and temp is below -10C, or colder.
I still have the steelies, VW dealer gave me the brush off when I took in the letter I received from VW Canada.I was told it is OK as long as it eventually starts then you are ok....and now the recall has expired...
I believe my current problem can be fixed if the Glow plugs remain lit longer, and in order to fool the ECU with infinite reading from the ECT,
this apparently causes the ECU to keep the voltage on to plugs(via relay) for the maximum setting of 25 seconds or so, as stated on many threads I read on here.
So I built me a switch assembly, where I can flick a switch on, causing an open to the ECU from the ECT, then proceed with the normal starting procedure, this also lights up an LED to remind the me I am in the FOOL mode and to go back to normal once the engine starts and stabilize.
And while at it, I added a couple of other goodies, incorporated into the same assembly.
switch 1, controls the Fool mode on/off and turns the LED to the left.(as a reminder)
switch 2, is for a digital volt meter that will be installed in the blank space next to the driver's seat warmer switch.
switch 2 when up, it displays the car 12V supply from a switched source, the VM also provides the charging system health, and the condition of the battery during the GP cycle, cranking cycle as well.
switch 2 when down, measures the voltage supplied to the glow plug,(plug #1, is tapped as a source), and this position also doubles as Off position of the voltmeter display, as it may become a distraction at night, due to the bright blue display.
the 4 LEDs, to the right of this switch act as a visual indicators of voltage being supplied to plugs, tapping point is at GP harness.
(does anyone know if the source of the power/contact to the plugs is bridged for all 4, or each uses a separate relay contact ?
I bench tested it and it works as intended, but will not know for certain till installed and the weather falls below -10C, but it should not hurt, I hope !
Sorry guys, I am not sure how to attach a photo, maybe I do not have the permission yet, help if you can, maybe I can email it to a member who can. thx/ SAM
Switch 1 is DPDT
Switch 2 is SPDT
grounds for the LED use limiting resistors, the 12v on the left has a 470 ohm, the glow plugs Leds use 390 ohm.
a picture is worth a thousand words, I wish I knew how to post one.
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