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Large MPVs -- Ford Galaxy / VW Sharan / SEAT Alhambra: => Mk3 Ford Galaxy / Ford S-Max => Topic started by: chabadav on June 12, 2021, 03:50:16 PM

Title: Park sensor still not working even after replacing entire rear wiring loom
Post by: chabadav on June 12, 2021, 03:50:16 PM
For over a year now the park sensors have not been working on my 2007 Galaxy.
Engaging reverse results in rapid blinking of button on dash.
I replaced a couple of sensors because they were scratched but did not help and then saw that one of the 3 wires going into one of the sensors was brocken.
I ordered a complete new loom from (eBay, used) as could not repair properly - break in wire was too close to socket.

Installed and still not working!!
I unplugged battery so should have had a chance to reset everything.

The front wiring loom and sensors seem OK

Any ideas what else I can try?
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: johnnyroper on June 12, 2021, 04:01:32 PM
First thing is plug diagnostics in and see what codes have been logged to point you in the right direction
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: SirDavidAlhambra on June 12, 2021, 05:37:16 PM
Frankly I’d just turn them off. Probs not worth bothering about in a 14 yr old car? As amazing as they are, chances are it will be at the scrappers within the next 6 years. My life became a lot easier with cars when I learnt not to fret about small stuff like dings, dents and parking sensors
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: chabadav on June 12, 2021, 06:25:22 PM
First thing is plug diagnostics in and see what codes have been logged to point you in the right direction
I only have one of those bluetooth OBDII dondles and "EOBD-Facile" App on my iPhone. Will that allow me to run a diagnostics scan?
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: chabadav on June 12, 2021, 06:26:38 PM
Frankly I’d just turn them off. Probs not worth bothering about in a 14 yr old car? As amazing as they are, chances are it will be at the scrappers within the next 6 years. My life became a lot easier with cars when I learnt not to fret about small stuff like dings, dents and parking sensors
Thanks for your opinion but does not help me very much.
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: johnnyroper on June 12, 2021, 06:39:10 PM
I only have one of those bluetooth OBDII dondles and "EOBD-Facile" App on my iPhone. Will that allow me to run a diagnostics scan?

Probably not you need to use something like forscan as that scans all modules in the car, the apps like you have tend to just do the engine
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: chabadav on June 12, 2021, 07:15:08 PM
Probably not you need to use something like forscan as that scans all modules in the car, the apps like you have tend to just do the engine
OK, Thanks! I can only find FORScan Lite for 6,99 EUR on App Store so will try that once downloaded.
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: SirDavidAlhambra on June 12, 2021, 08:33:17 PM
Will it be fully compatible with an OBD2 scanner?  [GL]
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: brianh on June 12, 2021, 08:52:35 PM
Your more likely to get some luck with a laptop and the windows version of forscan. If you have a laptop with bluetooth you might (and I'd stress the might bit!) get that to work with your adaptor. If not then the usual cable to use with Forscan is one like this https://www.ebay.co.uk/itm/181457167332 with the switch on it.

Forscan windows program is free to use, but needs a license for some bits (not the bits your dealing with though, only PATS and something else I think, and a free 2 month license can be obtained for those functions if needed)

Forscan as said above is your best bet for diagnostics on these either way. Only other thing I can suggest is a multimeter test of the loom if you haven't already done so. You'd hope that a used loom off ebay would be tested, but some folks idea of testing something or fully working is questionable at best (as I discovered with "fully working" door lock motors which had me chasing round the car for a wiring fault to find I'd actually been provided with no less than 3 different used lock motor units and the original one all of which were faulty, provded by plugging into a working door loom on another door where the fault still persisted).
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: chabadav on June 13, 2021, 10:18:50 AM
Your more likely to get some luck with a laptop and the windows version of forscan. If you have a laptop with bluetooth you might (and I'd stress the might bit!) get that to work with your adaptor. If not then the usual cable to use with Forscan is one like this https://www.ebay.co.uk/itm/181457167332 with the switch on it.

Forscan windows program is free to use, but needs a license for some bits (not the bits your dealing with though, only PATS and something else I think, and a free 2 month license can be obtained for those functions if needed)

Forscan as said above is your best bet for diagnostics on these either way. Only other thing I can suggest is a multimeter test of the loom if you haven't already done so. You'd hope that a used loom off ebay would be tested, but some folks idea of testing something or fully working is questionable at best (as I discovered with "fully working" door lock motors which had me chasing round the car for a wiring fault to find I'd actually been provided with no less than 3 different used lock motor units and the original one all of which were faulty, provded by plugging into a working door loom on another door where the fault still persisted).

Thank you! I have ordered a similar OBDII cable for Ford with a switch on the OBD connector. What is the switch for?
I have an old windows laptop lying around so will use that (I am a Mac user).

I did not test the resistance of the bought loom with a multimeter but you are right and one should not assume that used items have been tested by the seller beforehand.
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: SirDavidAlhambra on June 13, 2021, 10:51:19 AM
The switch flicks between basic obd2 and enabling the features specific to fords. I use mine very regularly. For instance, I used it to enable fancy new features.

 8-) 8-) 8-) 8-) 8-) 8-) 8-)
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: brianh on June 13, 2021, 03:35:26 PM
It switches between HS and MS can - more detail on the Forscan forum here > https://forscan.org/forum/viewtopic.php?f=4&t=6142

Some systems use hs, others use ms (potentially on the same vehicle). Other adaptors will do that switching automatically, but may cost a lot more. Ultimately your looking to use it to sort this issue out and potentially keep for use in the future if you need it, so it should be adequate for those purposes.

Older windows laptop should be fine as long as its running windows 2000 or later (so XP, Vista, 7,8 or 10 should all be fine as well). windows 95/98/me would not, though I doubt many laptops of that era still work anyway.
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: chabadav on July 12, 2021, 12:27:19 AM
Thanks for all your advice.
I eventually got the connector as well as a computer running FORScan and ran a diagnostics test today.

There were 9 independent DTC`s for PAM:

2 for the power circuit:
B1B58:11-2F > Rear sensors Power Circuit (circuit short to ground)
B1B57:11-2F > Front sensors Power Circuit (circuit short to ground)

and these for the sensors:
B1B42:96-68 > Left Front Inner sensor - component internal failure
B1B44:01-6C > Righr Rear Outer sensor - general electrical failure
B1B46:01-6C > Righr Rear Inner sensor - general electrical failure
B1B48:01-6C > Left Rear Outer sensor - general electrical failure
B1B48:96-68 > Left Rear Outer sensor - component internal failure
B1B50:01-6C > Left Rear Inner sensor - general electrical failure
B1B50:01-6C > Left Rear Inner sensor - general electrical failure

This seems like some sort of control module fault to me as there are so many separate faults, both front and rear.
Should I perhaps try to get a replacement parking distance control module like this one:
https://www.ebay.co.uk/itm/FORD-S-MAX-2006-2014-MK1-PARKING-DISTANCE-CONTROL-ECU-MODULE-8G9215K866AA-/353392064591?var=0&mkevt=1&mkcid=1&mkrid=710-53481-19255-0&campid=5338268676&toolid=10044&customid=Cj0KCQjwraqHBhDsARIsAKuGZeG-Lk7PwLujUlri90-CEraSK_fz4O1LBEO9ASbsft0aHUqDCF6BVRUaAqNlEALw_wcB (https://www.ebay.co.uk/itm/FORD-S-MAX-2006-2014-MK1-PARKING-DISTANCE-CONTROL-ECU-MODULE-8G9215K866AA-/353392064591?var=0&mkevt=1&mkcid=1&mkrid=710-53481-19255-0&campid=5338268676&toolid=10044&customid=Cj0KCQjwraqHBhDsARIsAKuGZeG-Lk7PwLujUlri90-CEraSK_fz4O1LBEO9ASbsft0aHUqDCF6BVRUaAqNlEALw_wcB)


Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: Mirez on July 12, 2021, 10:49:51 AM
I'd be looking to measure and/or rectify the power issue first. A poor ground or low voltage issue will cause the sensors to report issues which might not be present.
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: SirDavidAlhambra on July 12, 2021, 10:53:31 AM
Very wise advice
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: chabadav on July 12, 2021, 11:40:06 AM
I noticed that the battery reading on FORScan was 11.7V - is that too low?

Where are the ground wires located for the park distance control system? How can I check?

Sorry for the dumb questions but I am not so experienced with electronics - I am more of a basic mechanic handyman
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: Mirez on July 12, 2021, 01:42:26 PM
11.7 is low but not too low (unless the engine was running) so it shouldn't be triggering an issue with that.

You'll need a multimeter to test it properly, then pop a plug off one of the sensors and probe the wiring. You should have a supply and a ground plus a signal wire.
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: chabadav on July 12, 2021, 04:10:45 PM
I checked the voltage (set to 200 mA) of all fuses and all were OK (reading was 0) apart from the one for the diesel filter heater (F14, 15A), which showed a value of -2.0. Strange that I had to change this earlier this year, so obviously fault in car wiring somewhere. Filter heater connector looked fine.

With respect to the PDC, I just had a closer look at the rear fuse boxe and found it strange that the 5A fuse in the rear box for position FB8 was empty - thus is the only one supposedly for the PDC electronics.
There was a 5A fuse in position FB1 that is apparently something to do with sun blinds, so I changed its position from FB1 to FB8.
I then disconnected the battery fro a while, cleared all DTC codes and rescanned. An error came for the PAM stating it could not be read so I put the 5A fuse back to position FB1 and scanned again after clearing.
This time only two faults codes came for the PDC:
[attach=1]


So, only problems with rear and front power circuit remain (circuit short to ground). All other error codes were gone for the sensors. I did switch them on before running the scan again.
Not sure why the fuse plan I was referring to is obviously wrong for my model/year of car...

[attach=3]

I also had a look at the PDC module and all wires/connectors looked OK:
[attach=2]

So, how do I now test all the connectors that come into the module using my voltmeter?


Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: chabadav on July 12, 2021, 04:20:25 PM
sorry, forgot to show positions of FB1 and FB8 on the rear fuse box:
[attach=1]
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: chabadav on July 12, 2021, 04:23:22 PM
11.7 is low but not too low (unless the engine was running) so it shouldn't be triggering an issue with that.

You'll need a multimeter to test it properly, then pop a plug off one of the sensors and probe the wiring. You should have a supply and a ground plus a signal wire.

I am not really sure what you mean by supply, ground and signal wires. What should I touch with the 2 multimeter pins?
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: johnnyroper on July 12, 2021, 05:56:13 PM
I am not really sure what you mean by supply, ground and signal wires. What should I touch with the 2 multimeter pins?

Each sensor has 3 wires one is power supply,one is Earth (shared power and Earth for all sensors) then the third wire is the signal wire back to control unit from the sensor.
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: Mirez on July 12, 2021, 09:03:50 PM
200ma is a current setting, you want to put the meter in DC Volts then put one side of the meter to a ground point (Door hinge or other non painted metal) and the other side to one of the pins, try all three until you get a voltage reading.

Then put the meter in resistance mode (Ohms - look up the symbol) and repeat the process which will identify the ground.
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: chabadav on July 12, 2021, 10:20:29 PM
Sorry,  did not read properly that you were referring to the actual parking sensor wires, I was referring to the wires (pins) on the PDC control module and the corresponding connectors.
There does not seem to be any faults with the sensors themselves after my last scans...
Should I still test each sensor connector?
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: johnnyroper on July 12, 2021, 10:45:05 PM
If you locate the supply to sensors and measure that to ground on resistance,can do it from plug on pdc module. The smaller plugs will be for sensors one for rear and one for front can’t recall which is which,in the plug there will be 4 signal wires a power supply and an Earth (most likely brown I think) I can’t remember wire colours but have a look at a couple of sensors and identify common colour to each one that will be the power supply. Measure from Earth to power in the plug with it disconnected if there’s resistance unplug each sensor in turn see if it changes To eliminate sensors.  If fault still present with all disconnected you have fault in loom. If you find no issues then suspect the control unit.
Do same for front and rear as code is showing for both.
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: chabadav on July 13, 2021, 11:01:14 AM
Thank you, I will try to check all the wires as you describe.
I did look carefully at all the connections to sensors (both front and rear) and they seem fine. The entire front and rear wiring looms also seem fine as well as the connectors joining them to the cars wiring that presumably leads directly to the PDC module at rear left. I cannot imagine there would be a problem with wiring there as the wires are mostly hidden within car and not really exposed to possible damage.
This is why I was thinking the most likely reason would be the PDC module itself and was wondering how best to test this module.
Title: Re: Park sensor still not working even after replacing entire rear wiring loom
Post by: johnnyroper on July 13, 2021, 11:38:10 AM
You can’t really test the module itself all you can do is test the wiring and sensors for the supply shorting to ground and if that checks out process of elimination would say the control unit is at fault