Brake Pedal Sensor Issues

[Kevinb]

Hi everyone,

 

Okay, so I started having intermittent issues with my brake pedal sensor. After a bit of research, I discovered the old "pull out the sensor arm" trick but it seems to have stopped permanently now. I ordered a part from Ford and received the part 1c0 945 511 a - a much larger unit in green. I didn't argue as I couldn't envisage the brake pedal area.

 

Upon fitting it, I've found the area just isn't large enough to allow the unit to rotate in place. I gets jammed in the steering linkage surround. I notice there is an white inner mechanism that spins when it is turned clockwise - and will only go clockwise. My gut is telling me it's the wrong part. Can anyone advise?

 

The original part number is 1j0 945 511 a but I do understand that a manufacturer redesigns things retrospectively as necessary. I've attached some pictures showing the new part, it in place, and then the old (black part) in place as well.

 

Help anyone before I do my nut in!

 

Cheers!

[BrianH]

I think you can do it by pushing the pedal down. You might need to start the engine to gain the vacuum assist to do it. The different sensors do exist. There's some info elsewhere on here I think the green one is an improvement on the black one. What's your symptoms for thinking it's at fault? Flashing glow plug light is the usual fault. If the lights aren't coming on once you've swapped it check the wires in rear hatch door gaiter.

[Kevinb]

Hi BrianH,

 

I'm pretty convinced it's the sensor as I have been able to workaround the problem by depressing the pedal, and then pulling out the sensor arm, and then gently letting out the pedal. This usually works within a couple of attempts. However, it is getting worse. Hence my need to fix it. The flashing glowplug sensor is usually the indication but also when the rear lights don't go out when the car is first turned on.

 

I am aware that (presumably) VW redesigned the part at some point, which is why I didn't argue at the dealership. However, I have seen them get things wrong in the past....

 

I don't think the new (green) part is the correct unit as, although it does fit into place, you can only turn it clockwise due to two lugs directly behind the locating/retaining pins (not present on the old unit). From what I can gather, these "activate" the unit and prevent it from being turned anti-clockwise - the way the old unit is located into position. Due to the new unit being significantly larger than the old unit it sits pretty much completely flush with the steering column surround (which lips outward at the top). Due to the way the parts sit (steering column and sensor) the sensor can't be twisted around. It's not a case of me not having the minerals (I'm a fairly hefty presence) to turn it, it simply will not turn.

 

I did fit the electrical connector to test it in desperation but it didn't solve the problem either. I know this isn't necessarily a foolproof diagnostic, but may be be relevant.

 

Fortunately, I was able to coax the old unit into working again...

 

The new unit's part number is 1c0 945 511 a

and the old unit's part number is 1j0 945 511 a 

 

This does mean that it is possibly the right part but still, from a mechanical point of view, it just doesn't fit!

 

 

Problems problems!

Edited September 3, 2015 by Kevinb

[BrianH]

This is worth a read if you haven't already discovered it

 

http://www.fordgalaxy.org.uk/ford/index.php?/topic/8351-fitting-a-new-brake-light-switch/&do=findComment&comment=63453

 

This possibly relevant as well

http://www.fordgalaxy.org.uk/ford/index.php?/topic/27038-help-pre-holiday-problem/?hl=%2Bbrake+%2Blight+%2Bswitch

 

The second one is the reason i'd suggested starting the engine and pushing pedal down as that seemed to work for him, although the auto may be different?

[Kevinb]

Brian,

 

Cheers for the info. I've got a manual Galaxy.

 

The first link pointed out it's a pain to fit. They weren't wrong, it's a complete bastard to twist into place.

 

Missus took matters into her own hands and ordered a part from Ebay, which arrived today. After a little bit of swearing, straining, spilt blood and much effort, it still refused to twist in place. A pair of grips later for the leverage and it turned into place!

 

All working ok now but I do have concede that Ford were probably right and it was the right part after all. Still, it works fine now.

 

Just the starting issue to sort out now.

 

 

I greatly appreciate your input on this.