CEM clean now PS (EPS) pump on all the time
 

An unusual condition has occurred on our 2005 2.0d s40 not the 'common' power steering failed but instead our power steering pump is on constantly, engine on or off, car unlocked or locked....

Some background about how this started....

I had the brake failure stop safely message and then a whole host of other messages and ultimately the car wouldn't accelerate and then stalled. There were no issues or warnings with the steering.

Following some research it pointed to poor connections on the cem under the glove box. I took it out and cleaned every connector, relay and fuse using electrical contact cleaner and then reassembled.

When I connected the battery I could hear what sounded like a relay clicking at the front of the car near the radiator and net headlight. Then I could hear the steering pump had activated (while I was tightening up the 10mm battery terminal).

I disconnect the battery, took out the battery, air box and checked the wiring to make sure the loom hadn't chafed on the gearbox or chassis. I checked and cleaned all the connections, fuses and relays in the fuse box next to the air box and reassembled. After a couple of minutes the pump activated again.....

Help please....

I'm at a loss of what to check next.

Just a shot in the dark here, but maybe a faulty relay ?
I would guess problem originates from CEM sending the signal when it shouldnt, but maybe relay somehow can be a culprit?

Im guessing you dont have anyone close by with Vida+Dice?

You will probably find corrosion in the power steering pump plug and socket affecting the network system ..., there is a repair kit available ...

Thank you for the suggestion. I cleaned the relays but didn't try swapping any, I'll try swapping them when I get home tonight.

One thing I still haven't done is to take the ecu(ecm?) Out of the wheel arch and check the connections there. I'll be doing that tonight too.

Unfortunately I don't know of anyone with vida dice near me in Birmingham. I might just order one as I will be sticking with Volvo for the family car going forwards (even though have had more than my fair share of problems with this one, I really like how comfortable they are plus the focus on safety)

Thank you for your help Clan, I did come across a thread last night about pump 'failure' due to this.

I'll pull the bumper off and check for this too.

I meant the main heavy duty plug on the pump itself ….

For some reason only lizardofbodom's reply was showing on my phone when I replied first.

I'll definitely be checking on the pump side too tonight. Am I right I thinking that it can only be accessed by taking the bumper off?

yes best to take the bumper cover off . There is a constant heavy duty power supply going to the pump ..

Thanks for the help so far. It took me until today to get around to looking at it...

Both connectors on the pump were very clean on the inside. I still cleaned it with contact cleaner and left it to dry while I took out the ecu from the nsf, the connectors looked clean in there too but again I used electrical contact cleaner and then re-assembled everything.

I also cleaned the three connectors below and to the left of the cem(behind the carpet and plastic cover.

... started fine no errors so I drove it to the end of the road and back. As I was about to park back up the steering momentarily went heavy and the power steering message popped up on the dash. The steering was back to normal straight away and the message also went away.

I haven't driven it since but I don't think I've 'fixed' it yet.

I also swapped the relays about in the engine bay fuse box.

Any other suggestions?

Have you tried to unplug and plug again CEM connections??