FBH running randomly help !

[willster]

Ok , so I installed my fbh and gsm activation recently, all working great no problems .
However last night after I activated it by phone for 15min and took a drive out , on my return about 15 minutes after I was back in the house I hear it fire up outside ! at first I thought it must be a fault with my gsm unit but I took this out and the fbh continued to run then cut out then start again when the coolant dropped temp . It was raining cold and dark so I just pulled the fuse and decide I would do some research before I try any fault finding .
Also I had already cut and insulated the k-bus wire on pin 2 when I installed the fbh , so doubt this could be causing any problems .Also I have the earlier PCB the c one not the b . If anyone can offer any advice I would greatly appreciate it . Also the airbag light was flickering as the fbh ran , ignition was off . Thanks

[klarzy]

Ok , so I installed my fbh and gsm activation recently, all working great no problems .
However last night after I activated it by phone for 15min and took a drive out , on my return about 15 minutes after I was back in the house I hear it fire up outside ! at first I thought it must be a fault with my gsm unit but I took this out and the fbh continued to run then cut out then start again when the coolant dropped temp . It was raining cold and dark so I just pulled the fuse and decide I would do some research before I try any fault finding .
Also I had already cut and insulated the k-bus wire on pin 2 when I installed the fbh , so doubt this could be causing any problems .Also I have the earlier PCB the c one not the b . If anyone can offer any advice I would greatly appreciate it . Also the airbag light was flickering as the fbh ran , ignition was off . Thanks

can you sketch out the wiring you used ??

[willster]

I will do a drawing and post it but the problems were evident when I took out all the wiring to my phone activation unit so its just the original 2 pin power to the fbh and the 6 pin with k-bus wire cut and insulated . I thought it could be a falut with the temp sensor forcing it to run but it still shouldn't run with ignition off so im a bit stumped. going to go and put the fuse back now, but don't have a 12v test light or anything so if it happens I wont really be able to see if there is 12v coming to pin one ,should be easy to test though as I have a choc block inline for pin 1's wire as that's how I wired my phone activation. just need to get a test light. Part of me thinks the pcb has gone mental ??

[David Lawrence]

I believe you are describing k bus activity triggering the random behaviour. My advice would be to cut the red/white wire at the 6 pin connection and secure it taping up the ends.

I'm some distance from the car right now but from memory that is pin 2 of the connection

[steveo]

Hi
Mine was the same
It was below 5 degrees and unless you have removed the sensor trigger wire it will fire up randomly until it reaches a required temperature this will continue every time the coolant temperature drops below the limit.
Steve

[FrenchMike]

Ok , so I installed my fbh and gsm activation recently, all working great no problems .
However last night after I activated it by phone for 15min and took a drive out , on my return about 15 minutes after I was back in the house I hear it fire up outside ! at first I thought it must be a fault with my gsm unit but I took this out and the fbh continued to run then cut out then start again when the coolant dropped temp . It was raining cold and dark so I just pulled the fuse and decide I would do some research before I try any fault finding .
Also I had already cut and insulated the k-bus wire on pin 2 when I installed the fbh , so doubt this could be causing any problems .Also I have the earlier PCB the c one not the b . If anyone can offer any advice I would greatly appreciate it . Also the airbag light was flickering as the fbh ran , ignition was off . Thanks

No worries ,if you're sure it's the first type ,then no kbus interface.
Normally the burner start when :

-external temp lower than 5 degrees
-coolant temp lower than 77 degrees.

Is you engine temp correct ? (88 deg via OBD)

Is the airbag light flickering only while the glowplug phase (first 2 minutes)

Mike

Mike

[David Lawrence]

Didnt read the line about you having already cut the k bus wire, sorry for the useless contribution.

Im wondering how you removed the gsm unit. Did you remove all wiring or just the unit. If the wire from the unit to the trigger pin is shorting on the body or not? I assume that you have a wire from the cabin to the fbh somewhere, and if it can be frayed or something.

This might be useless also but worth checking.

could you perhaps put a volt meter on its trigger wire to see if there is a spurious signal reaching it or if the unit is turning on in the total absense of an external trigger.

[willster]

No worries ,if you're sure it's the first type ,then no kbus interface.
Normally the burner start when :

-external temp lower than 5 degrees
-coolant temp lower than 77 degrees.

Is you engine temp correct ? (88 deg via OBD)

Is the airbag light flickering only while the glowplug phase (first 2 minutes)

Mike

Mike

Mike thanks for your response , yes its definitely the earlier PCB as the burner did have the later PCB and I swapped it as I wanted the trigger to ATC rely on pin 4 to come on at 30degrees not straight away like on the later PCB's.
Just to re-cap the airbag light was flickering with ignition OFF and the FBH was running , outside temp was not below 5 deg . Engine temp was 74 deg .
My thermostat is ok , I have a top hose one I added in the lest few months and it opens around 90degrees .
So last night I put the fuse back in for the fbh and this morning when I started the car the burner did not come on as supposed to despite the external temp being 2 degrees . However my battery light illuminated and stayed on red for my journey to work, I checked the voltage on the dash and it was fluctuationg betwwen 13.9 and 14.2 all the way so I presume all is well there . When I got to work I tried switching the ignition off and on to see if the battery light cleared , it did not. I guess this could be related to my fbh but im, not sure how .

[willster]

Didnt read the line about you having already cut the k bus wire, sorry for the useless contribution.

Im wondering how you removed the gsm unit. Did you remove all wiring or just the unit. If the wire from the unit to the trigger pin is shorting on the body or not? I assume that you have a wire from the cabin to the fbh somewhere, and if it can be frayed or something.

This might be useless also but worth checking.

could you perhaps put a volt meter on its trigger wire to see if there is a spurious signal reaching it or if the unit is turning on in the total absense of an external trigger.

Davis thanks for your reply . I removed the phone activation leaving the wires in but taped up the ends securely .That was my first thought that the trigger wire on pin 1 was getting 12v from somewhere, I will buy a DC multimeter today I think so I can check this . there is no wire to the cabin , my phone activation unit sits in the battery compartment or did.
As I said to Mike earlier I replace the fuse and the burner didn't fire up this morning like it should with outside temp below 5 and ignition on . I did however have a battery light on for some reason despite my voltage showing the alternator was charging ok ?? Bit stumped but I will get to the bottom of this eventually .

[FrenchMike]

Mike thanks for your response , yes its definitely the earlier PCB as the burner did have the later PCB and I swapped it as I wanted the trigger to ATC rely on pin 4 to come on at 30degrees not straight away like on the later PCB's.
Just to re-cap the airbag light was flickering with ignition OFF and the FBH was running , outside temp was not below 5 deg . Engine temp was 74 deg .
My thermostat is ok , I have a top hose one I added in the lest few months and it opens around 90degrees .
So last night I put the fuse back in for the fbh and this morning when I started the car the burner did not come on as supposed to despite the external temp being 2 degrees . However my battery light illuminated and stayed on red for my journey to work, I checked the voltage on the dash and it was fluctuationg betwwen 13.9 and 14.2 all the way so I presume all is well there . When I got to work I tried switching the ignition off and on to see if the battery light cleared , it did not. I guess this could be related to my fbh but im, not sure how .

So,forget the engine temp .
for info,the 12 volt applied on pin 1 comes from

the thermoswitch (engine running ,alternator ON)

54590

For the first 2 minutes ,12 Amps are drawn ,(glow plug)
then 3 Amp (fan and circul pump).

Check your battery voltage at rest .

54591

Mike

[willster]

So,forget the engine temp .
for info,the 12 volt applied on pin 1 comes from

the thermoswitch (engine running ,alternator ON)

54590

For the first 2 minutes ,12 Amps are drawn ,(glow plug)
then 3 Amp (fan and circul pump).

Check your battery voltage at rest .

54591

Mike

Thanks Mike , very detailed information there. I must admit the wiring diagram is slightly beyond me but I get the general idea of it.
I will check the battery voltage at rest , is this best done at the terminals with a multimeter or can I do it on the dash diagnostics? Thanks

[FrenchMike]

is this best done at the terminals with a multimeter or can I do it on the dash diagnostics? Thanks

It doesn't matter :}

[willster]

It doesn't matter :}

I have obtained a dc multimeter and will test my resting battery voltage later on . I have had a bit of a flashback of when I disconnected my gsm from the fbh after it started running on its own , I accidentally shorted the some of the wires , I guess the +12v I tapped off the fbh 2 pin and the ground I tapped off it too . I hope this hasn't killed my battery and or fbh ??

[David Lawrence]

I have obtained a dc multimeter and will test my resting battery voltage later on . I have had a bit of a flashback of when I disconnected my gsm from the fbh after it started running on its own , I accidentally shorted the some of the wires , I guess the +12v I tapped off the fbh 2 pin and the ground I tapped off it too . I hope this hasn't killed my battery and or fbh ??

I am not entirely sure what you did there but i do know for sure that if the K bus wire on the car side of your cut is grounding out intermittently then unpredictable things happen in the car such as lights coming on by themselves and warning lights on the dash etc, so hopefully just clear the fault and it should be fine. I dont think it does much to the FBH but it does upset the car.

I dont have an early model FBH but with the later type when the car wakes up, and while the car is between doors locked and go to full sleep which can take quite a while, the k bus activity makes the heater do silly things, but since you have cut that wire then you may have 2 faults. A grounding k wire upsetting the car, and a spurious trigger on pun 1 activating the heater.

If you could post any photos of your wiring splices etc, we might spot something to help you.

[willster]

I am not entirely sure what you did there but i do know for sure that if the K bus wire on the car side of your cut is grounding out intermittently then unpredictable things happen in the car such as lights coming on by themselves and warning lights on the dash etc, so hopefully just clear the fault and it should be fine. I dont think it does much to the FBH but it does upset the car.

I dont have an early model FBH but with the later type when the car wakes up, and while the car is between doors locked and go to full sleep which can take quite a while, the k bus activity makes the heater do silly things, but since you have cut that wire then you may have 2 faults. A grounding k wire upsetting the car, and a spurious trigger on pun 1 activating the heater.

If you could post any photos of your wiring splices etc, we might spot something to help you.

David thanks, I am going to have a fiddle later on and get some pictures on. The k bus wire is very well insulted with tape either end of the cut so doubt it is that. But wouldn't hurt to check this and re do it. I will post the results of my testing later on, thanks to everyone so far with all the help.

[HarryM1BYT]

Long shot...

I wonder if the OP has checked the plenum for water. The signal to run the FBH to say the engine is running, comes from the Engine ECU. Might the ECU and its plug have suffered submersion and the signal to run is a result of that submersion?

[willster]

Long shot...

I wonder if the OP has checked the plenum for water. The signal to run the FBH to say the engine is running, comes from the Engine ECU. Might the ECU and its plug have suffered submersion and the signal to run is a result of that submersion?
Thanks for your reply and advice. The plenum is dry and clear. It seems more than coincidental that this battery light has come on after I had the phantom burn on the fbh. I have test results from multimer and pictures which I will upload this evening at work and hopefully someone can point me where to go next with this. Thanks all

[willster]

Ok ! so I have made a bit of a breakthrough! Firstly I checked my voltage at rest on the battery with a meter, car hadn't been used for a few hours. Came in at 12.75 V so all ok there .



Next I decided to try the voltage on pin 1 of the fbh 6pin connector with ignition off ,it showed 2 volts . Then I decided I would turn the engine on and check nto see if it was or wasn't getting the 12v from the temp sensor to activate it , as the temp was 2 degrees in theory I should have gotten 12v onto this pin 1. I instead got 5.5 V with the engine running so I guess this extra volts is just from the alternator kicking in ? So I think that explains why it wont run on its own with the signal from the temp sensor, but not sure what to do next , how do I test the sensor?



Afetr I had done all this I decided to see if I could force the fbh to run so I quickly wired back up my phone activation and fired it up , it ran perfectly and shut off when the 15min cycle was up. So im glad the burner is still all ok, and it hasn't done any more phantom running yet !
Now for the breakthrough with my battery light being on !! I Noticed the battery light was not on on my journey into work this eveing and the fbh was running a cycle I activated fro my phone . Good I thought ,its just gone away ! after exactly 15 minutes it came back on ! I made the discovery that when my phone activation is forcing the heater to run by putting 12V onto pin 1 the battery light is off , then when the relay opens on my phone unit and stops the 12V the battery light comes on!!! I don't quite know what this means and when I first installed the unit it certainly wasn't doing this and the battery light wasn't on . Can anyone help me with what to do next ? Thanks
Pic of my wiring below
http://i1233.photobucket.com/albums/ff400/willster4/r754_zpsz4v1uyag.jpg
http://i1233.photobucket.com/albums/ff400/willster4/r753_zpszqd7cgce.jpg

[FrenchMike]

Hi,
Nice GSM ! any link ?

The thermoswitch is situated behind the front bumper (the round one).

It acts as a switch closed when it's temperature is lower than 5 degrees

Before all ,check the connections ;they are prone to become oxidized

Mike

[willster]

The thermoswitch is situated behind the front bumper (the round one).

It acts as a switch closed when it's temperature is lower than 5 degrees

Before all ,check the connections ;they are prone to become oxidized

Mike

Ok thanks Mike il have a look now .

[willster]

Link here Mike , I relly like the unit , very easy to set up and I can even make calls on it ! Led out and switch out. Only one Relay though. Cheap too
http://www.ebay.co.uk/itm/EBERSPACHER-WEBASTO-GSM-CONTROLLER/321917357077?_trksid=p2047675.c100011.m1850&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%2 6asc%3D20140107083358%26meid%3D2450a98e3bfa404f99d 46007bf54b0ca%26pid%3D100011%26rk%3D1%26rkt%3D1%26 sd%3D321890452469

[willster]

It has timed durations for the relay to be on so no need for a timer and also if you use an app like sms scheduler its as good as having a pre set timer as it just sends the message at a pre determined time and I can still be asleep !

[FrenchMike]

Link here Mike , I relly like the unit , very easy to set up and I can even make calls on it ! Led out and switch out. Only one Relay though. Cheap too
http://www.ebay.co.uk/itm/EBERSPACHER-WEBASTO-GSM-CONTROLLER/321917357077?_trksid=p2047675.c100011.m1850&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%2 6asc%3D20140107083358%26meid%3D2450a98e3bfa404f99d 46007bf54b0ca%26pid%3D100011%26rk%3D1%26rkt%3D1%26 sd%3D321890452469

Interesting for the price :}

[David Lawrence]

I would suggest to disconnect the signal wire going to pin 1 coming out of the gsm and test its voltage with the unit in both states. I am wondering if you have the wire coming from the common connection instead of its NO connection, and that the relay is trying to drag it down to 0v. That could be why you are seeing a funny voltange of 5.5v when the unit is off.

Test the voltage. In the on state it must go to 12v hence your battey light goes out, but in the off state it goes to 0v, but the alternator output is trying to drag it up to 12v so you get so ething in the middle depending on how the voltage from the gsm is being connected. Is it a relay or a solid state device of some kind?

Unfortunately those terminal descriptions are not very informative. Do you have a wiring diagram for it in english?






Ok ! so I have made a bit of a breakthrough! Firstly I checked my voltage at rest on the battery with a meter, car hadn't been used for a few hours. Came in at 12.75 V so all ok there .



Next I decided to try the voltage on pin 1 of the fbh 6pin connector with ignition off ,it showed 2 volts . Then I decided I would turn the engine on and check nto see if it was or wasn't getting the 12v from the temp sensor to activate it , as the temp was 2 degrees in theory I should have gotten 12v onto this pin 1. I instead got 5.5 V with the engine running so I guess this extra volts is just from the alternator kicking in ? So I think that explains why it wont run on its own with the signal from the temp sensor, but not sure what to do next , how do I test the sensor?



Afetr I had done all this I decided to see if I could force the fbh to run so I quickly wired back up my phone activation and fired it up , it ran perfectly and shut off when the 15min cycle was up. So im glad the burner is still all ok, and it hasn't done any more phantom running yet !
Now for the breakthrough with my battery light being on !! I Noticed the battery light was not on on my journey into work this eveing and the fbh was running a cycle I activated fro my phone . Good I thought ,its just gone away ! after exactly 15 minutes it came back on ! I made the discovery that when my phone activation is forcing the heater to run by putting 12V onto pin 1 the battery light is off , then when the relay opens on my phone unit and stops the 12V the battery light comes on!!! I don't quite know what this means and when I first installed the unit it certainly wasn't doing this and the battery light wasn't on . Can anyone help me with what to do next ? Thanks
Pic of my wiring below
http://i1233.photobucket.com/albums/ff400/willster4/r754_zpsz4v1uyag.jpg
http://i1233.photobucket.com/albums/ff400/willster4/r753_zpszqd7cgce.jpg

[willster]

Thank you for the response , unfortunately I don't have any proper wiring diagrams that came with my gsm , the chap said its just a normal relay , whatever goes into PKZ1 coes out on PKZ2 when the relay is ON or shut so to speak .
Im not too worried the unit is causing me any problems as those tests I did where I was getting 5volts to pin 1 were all done without the gsm unit attached atall.

I had the ECM out this orning nd did some more tests with the help of French Mikes schematic , after I worked out the wiring codes / colours! The thermoswitch at the front bumper is operating fine opening and closing as it should , I belled it out with continuity setting. I was only measuring 3volts with ignition off on the connector from the brown and yellow wire, so I went further upstream and to the ECM. I was also only getting 3volts coming out of the ECM on the brown/yellow wire that is supposed to carry the 12volts to the instrument pack so the battery light isn't on and to thermoswitch for the fbh obviously . So I then turned my attention to the supposed source of this 12v and stuck a pin in the thin blue wire that comes fro the alternator, engine running I only got 6.7 volts so I guess this is my problem , im just not sure what to do next ??

[FrenchMike]

I see you have the fisrt type ,so you must have

-Kbus pin2 inoperative
-Normal starting by sending +12 from the ECM on pin1
-Parking heating by sending +12 from GSM on pin 3

I hope you haven't damaged your ECM sending an external +12 to it :shrug:

The black box included in the GSM looks like a classic relay

Mike

[HarryM1BYT]

The last person to have a false charge light on, traced it to a faulty wire leading to the Engine ECU. I suspect your charge light issue and the FBH randomly firing are linked, so it might be worth your trying to find that post in the forum about the charge light coming on.

Because your plenum is dry, it does not mean it has always been dry. Any immersion the ECU has suffered can subsequently cause some peculiar issues.

[willster]

Oh ok I get it, the thermo switch was previously open and that's why this problem has only just come to light. Because it was the first properly cold morning so the thermo switch went closed and I sent 12 v from my gsm onto pin 1 and all the way back to ecm and alternator. Doesn't the fact I only got 6. 7 volts from the alternator to the ecm? Surely that should be 12v? Thanks

[FrenchMike]

Oh ok I get it, the thermo switch was previously open and that's why this problem has only just come to light. Because it was the first properly cold morning so the thermo switch went closed and I sent 12 v from my gsm onto pin 1 and all the way back to ecm and alternator. Doesn't the fact I only got 6. 7 volts from the alternator to the ecm? Surely that should be 12v? Thanks

Pin1 receives 12 volt from the ECM across the thermoswitch .

It's not good to put an external 12 volt at the same point without diodes...

use the pin3

I fear your ECM is damaged :shrug:

[willster]

Thanks to everyone who has helped me get this far with my issue . Touch wood all other behaviour with the car seems ok so far so hopefully its just the pain of the charge light being on and obviously not having any oem function of the fbh from the thermoswitch. Unless I can run a non permanent live feed to the switch from somewhere else,but I doubt I will bother. Lesson learned , think bout the wider implications of firing current to places you don't fully understand . Harry thanks I found the thread you mentioned about and will check the wiring but I do feel its related to me putting 12v on pin 1 , and the thermo switch closing . But I will be checking the wire for damage as best I can as a long shot. Thanks