Rear air suspension problem 2003 E270
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2003 E270 wagon R/H drive
Rear air suspension problem 2003 E270
I'm a new poster here but have read and gleaned a lot of useful information, so I'll take this opportunity to thank all contributors. Now for my problem, I've looked here and elsewhere for help but so far no luck. Where is the fuse for the air suspension self levelling pump? I've just eplaced both the original rear struts with Arnots. I also stripped the pump and replaced the piston and "O" ring plus the air filter. All worked fine for about a week & 200 miles, then on my way home the dreaded red screen " Car too Low".
I've removed the pump and checked it, 12v to the motor and runs no problem, 12v to the solenoid, fired, no problem. All the connections are clean and none of the wiring to the pump from the car appears to be damaged.
Removed relayand tested, fed 12v to pins 85 –v,86 +v, & 30, pin 87 showed 12v when relay powered, tested resistances across pins 85 & 86 ( 85ohms) anything between 50 & 120 is OK (above or below shows relay faulty), and zero ohms with power on between pins 85 & 86 as it should be, so all OK.
But when you turn on ignition or start engine the pump won't run. Held the relay up in my fingers (very loose fit at back of fuse box, but all connections seem fine) but no click, so assume no feed getting to relay and assuming I'm testing the correct relay! The green relay at the rear of the fusebox on the drivers side (R/H drive) of the engine bay. See pics.
There is one 40amp fuse in fuse box which is intact. Is this the correct fuse or is there one situated elsewhere? Any ideas welcome.
I disconnected the battery for 2hrs in case there was a computer lockout to protect the pump from burning out if running for too long. No change.
Hey, I'll try anything, so if you have what you think is a valid suggestion then please post it.
Many thanks. John
Had a suggestion it could be the rear axle level sensor/s. I'll have look later and let you know.
.
I've removed the pump and checked it, 12v to the motor and runs no problem, 12v to the solenoid, fired, no problem. All the connections are clean and none of the wiring to the pump from the car appears to be damaged.
Removed relayand tested, fed 12v to pins 85 –v,86 +v, & 30, pin 87 showed 12v when relay powered, tested resistances across pins 85 & 86 ( 85ohms) anything between 50 & 120 is OK (above or below shows relay faulty), and zero ohms with power on between pins 85 & 86 as it should be, so all OK.
But when you turn on ignition or start engine the pump won't run. Held the relay up in my fingers (very loose fit at back of fuse box, but all connections seem fine) but no click, so assume no feed getting to relay and assuming I'm testing the correct relay! The green relay at the rear of the fusebox on the drivers side (R/H drive) of the engine bay. See pics.
There is one 40amp fuse in fuse box which is intact. Is this the correct fuse or is there one situated elsewhere? Any ideas welcome.
I disconnected the battery for 2hrs in case there was a computer lockout to protect the pump from burning out if running for too long. No change.
Hey, I'll try anything, so if you have what you think is a valid suggestion then please post it.
Many thanks. John
Had a suggestion it could be the rear axle level sensor/s. I'll have look later and let you know.
.
Last edited by John Harries; Sep 29, 2017 at 07:33 AM.
