2013 Aygo Power Steering Fault after hitting a pot hole.

[BurntOrangeAygo]

Hello,

I've had my Aygo fire since new in 2013. It has been a great little car to zip about in. Two days ago I hit a pot hole and the car shuddered, when I looked at the console I saw P/S light had come on. I took it to the Toyota Garage I bought it from and the mechanic said that the power steering was working but had switched itself off. He reset the fault, but said that if the light was to come on again it would mean I need a new power steering ECU. But, driving home it was working fine and I had working steering just like normal.

The next day I start the car up and no power steering again! Unfortunately I had to drive around without it all day which was tough but doable. I took it back to the garage after work and was informed that they could order the part but it would cost around £500! Obviously i was abit shocked, I told them I couldn't afford that and the car isnt worth more than £2000. They did mentioned I might be able to part exchange it for Rav4 that a customer never collected after having work done to it.

So my options are to part ex my little Aygo, pay £500 and keep or buy a 2nd hand power steering ECU from eBay and either fit it myself or have a mechanic fit it. From my own research I've found that th power steering ECU is located in the center console behind the 12v cigarette lighter. I don't know how to remove the plastic cover and I don't know if the power steering ECU can be removed and then simple replaced. Does it need calibrating? If so I should take it to a mechanic and have him fit it right?

 

Thanks for any help you can offer, I would like to keep my little Aygo its a real workhorse (when its not being damaged by unrepaired roads).

[Planemo]

The Aygo does indeed need recalibrating after an ECU swop. Unfortunately failures in the ECU are not uncommon. This link may help:

http://www.c1oc.co.uk/forum/viewtopic.php

[Planemo]

Sorry, Try this link

[fordulike]

This might be a long shot, but you could try disconnecting the negative Battery lead, leave for half hour, then reconnect.

[BurntOrangeAygo]

I will have a look at how to disconnect the negative Battery feed. 

[fordulike]

2 hours ago, BurntOrangeAygo said:

I will have a look at how to disconnect the negative battery feed. 

Just to confirm, the actual Battery negative terminal, not the steering ECU.

Think it was something like a 12 or 13mm spanner, last time I disconnected my car Battery.

[fordulike]

Another thing that may or may not be related, check the car's charging system and Battery condition, as I've heard that low current feed to the power steering system can affect it somewhat.

Before I replaced my Battery with a new one, every now and again the steering would become slow and slightly stiff, like there was less assistance. l've had no issues since I popped a new Battery on. Battery was same age as yours when I replaced it.

[Mooly]

Why would hitting a pothole result in damage to an ECU ? That doesn't add up at all. Trying a 'Battery reset' is a good suggestion. 

[Planemo]

I was thinking that if enough of a force was applied to the track rod end, the ps motor might see a very high load/resistance and send a signal to the ps ecu that there was an issue. A bit like a failsafe. Eg if you locked up the front wheels completely and kept trying to move the steering wheel, would the ps motor just carry on trying to work and then burn out or would it sense a problem...and send that fault to the ecu? 

I may well be wrong and a loose Battery terminal is a good shout, but as I said these cars are not without their ps ecu problems. Far from it.

[BurntOrangeAygo]

I disconnected the negative end of the Battery and left it for 30 minutes but the power steering fault is still there. 

There was a sharp jolt when I hit the pothole so I imagine you are correct with your description of what happened. 

The Toyota garage were able to clear the fault in about 10 minutes but said it may return. That evening I was able to drive home with power steering but the next morning it was faulty again. It's strange to me that it was working okay when they had looked at it but sitting on the drive and then starting it up brought the fault back. 

Will it be worth getting a new ECU, the work is about £500 or so but my car is only showing as being worth about £2.5k on auto trader. Perhaps I should part ex it!

[fordulike]

I should imagine that the power steering ECU contains MOSFETS to control the power to the motor, so the theory of a current overload could be correct. This could have damaged one or more MOSFETS.

There's a boatload of used ECUs on eBay for peanuts, so it may be worth obtaining one and swapping it over with your existing one. Famous last words, but it doesn't look like a difficult job to me. Maybe access is a bit awkward, but doable.

Toyota Aygo Power Steering ECU

[Planemo]

Yep I would probably try a cheap used ECU as well, just remember that Toyota are probably the only people who can recalibrate it though.

[fordulike]

30 minutes ago, Planemo said:

Yep I would probably try a cheap used ECU as well, just remember that Toyota are probably the only people who can recalibrate it though.

Do they need recalibrating though? I would have though that you would just need to make sure the steering wheel and wheels are perfectly in the straight ahead position, then reconnect power.

[Mooly]

If you have Toyota replace the ECU, then I would ask for the old one back on the chance that if the problem recurs you have some form of redress and could ask for the original part to be refitted.

I have heard of power steering systems needing to be 'calibrated' but have no direct experience on that so wouldn't like to say. Calibration can mean a lot of things, anything from tweaking for optimum operation all the way through to telling the ECU which variant you have, type of rack, year of manufacture etc etc.

Don't be afraid to ask the dealer whether they are a straight swap or not.

 

    

 

[Cyker]

If it's going to be expensive, take pictures of the pothole and get the local council to foot the bill!
 

[ZelfZA]

Hi. 

My ECU's relays go haywire after a bump or two. I noticed that if I give it a good-ol "whack"it keeps quiet for a while.

It got to a point where while driving at 100 km/h, a bump would have it disable my power/steering.

Toyota gave me a quote for R3200 and they insist on putting the car on the computer. 

My word... Ive taped it in my hand while parked.. I know its just the ECU. 

Then I read a story about replacing the Relays and after searching a bit... R600 before import costs to get a relay. 

Have you opened the ECU? Have you seen how its put together? No Way!! Not Me!!

I had a jqc-3f relay from an Arduino project and I used some pliers to break out the faulty relay.

Alakazam.. It works...

I'll give it some time and let you you know if it goes South..

Regards