Parktronic fault?

[AlanD]

Had a look at a CLS55 today and was told the parking sensors weren't working on the rear. Turned out neither did, but I could do with some help guessing what the fault is.

When driving, the "P Off" light seems to come on itself, thus disabling Parktronic. When I try backing or edging forward up to a wall and press it again to turn it back on, a loud alarm beep sounds for about 2 seconds and both sets of internal position lights show two lights per side, but do not change depending on how close you are to something. Seems to tend to disable itself again then if you drive.

Ideas? Nothing came up on dash as an error.

 

[whitenemesis]

One or more senors have failed, the system self tests at IGN on detects the failed sensor(s) and shuts down.

 

[AlanD]

So it's relatively normal? That's a relief if so. Shame it couldn't just stick a relevant error message on the dash! Is it trial and error in the garage to fix then or will STAR tell the mechanic exactly what's at fault?

 

[whitenemesis]

STAR will pinpoint the errant sensor(s)

 

[Lenny63]

Very normal - but quite expensive to fix in the main

Approx £60 per sensor and then paint on top

Front is a bumper off job - rear easy enough

Was t a really really wet day ? Sometimes they can play up in the wet

By all means - no serious issue in the main

As our friend above states - star can diagnose per sensor

 

[KevM1979]

I have a W210 E55 & the sensors don't fault on start-up, but the rears only work on the passenger side, which I can't get my head around

 

[AlanD]

Completely dry day today. As I thought it was the rears only, I had a quote from PCS already. Hard without knowing how many have failed though! Could be £500 in just parts if all of them are duds!

The other fault is the two front door keyless-go handles don't work anymore (rears are fine). I guess I could live without that .. parking sensors are much more of a loss!

 

[Lenny63]

Alan -how about you ask
The dealer to take it to a local Indy at your expense to have them diagnosed via STAR so
You know what you're looking at ? Cost wise

Keyless go handles are just short of £200 per handle