ACE red light and ACE pump vibration

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LeaUK

New Member
Posts
100
Location
Essex
Hi Guys

After resolving the Three Amigos I'm back to my first issue of the ACE red light flashing after a 45 min journey (ish) followed by waiting at lights/traffic. A restart often removes it for a short period, or if I'm travelling at speed after a restart it will remain off until next pause.

Last year I replaced the ACE pump filter and fluid (with the correct versions) and all was well for over a year.

There are no fluid leaks and the ACE reservoir is full. No top up required since last year's replacement. :)

I will read the codes and update the thread, but just wanted a 'heads up' before heading to the garage.


1. Can the RED indicator be triggered by the ACE pressure transducer? Or does this transducer trigger just orange.

2. Will the accelerometers generate a RED indicator?

3. It would seem strange for an accelerometer failure as the RED light is only generated after 45 mins (ish) drive and pause - rather than upon cornering.

4. What triggers RED flashing?


Vibration from ACE Valve Block

I note a vibration/rumbling sound through 1-1.5k revs from the ACE Valve Block beneath the drivers door sill, whether in gear or neutral. It can be reduced by gripping two pipes emanating from the block.

I suspect my RED light and this vibration are linked :-(

Any pointers welcomed.

Cheers
Lea
 
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the red light comes on if there's a massive pressure loss in the system... so if it's vibrating too IMO the pump has a problem....i hope it's still under warranty...get it plugged in a tester to read the fault code to make sure
 
Uhm, the vibration isn't from the ACE pump, I was incorrect. I assumed the ACE pump was within the housing beneath the drivers seal where the ACE pipes congregate, but it seems driven by a belt therefore within the engine.

My vibration emanates from the ACE 'manifold' beneath the drivers side sill - perhaps a potential phew!
 
the red light comes on if there's a massive pressure loss in the system... so if it's vibrating too IMO the pump has a problem....i hope it's still under warranty...get it plugged in a tester to read the fault code to make sure

Or the filter gets blocked or perhaps an intermittent pressure sensor?

What do you think?
 
could be many things, the pressure transducer usually triggers the amber warning but depends on the output as ff the output is for extreme low pressure it could be red too... the real diagnosis is with tester...anyway you can rule out some issues observing the car's behaviour...is it in "locked bars" or "floppy" default mode while the warning is on? you can reduce the possibilities this way... check out the attachments
 

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Thanks for this useful info. I think I'm 'Torsion Bars Locked' as I can't really feel much change when turning.

Do you know where the accelerometers are physically located?

Thanks
Lea
 
you better download a RAVE from here http://www.myrangerover.co.uk/MyRangeRover/RAVE.html and start reading about the system if you want to DIY...the easyest way to find the fault is with tester though

RAVE said:
Accelerometers
Two accelerometers are used for the ACE system. The upper accelerometer is mounted on a bracket, behind the
headlining adjacent to the rear view mirror and the sunroof ECU. The lower accelerometer is located on a bracket on
the inner sill panel under the RH front floor.
The lower accelerometer is the primary sensor used to measure lateral acceleration of the vehicle for roll control. The
upper accelerometer is used by the ECU for roll correction and fault detection in conjunction with the lower
accelerometer.
Each accelerometer is a solid state capacitive acceleration sensor and operates on a 5 V supply from the ECU. The
upper and lower sensors can measure acceleration in the range of ± 1.10 g and return an output to the ECU of
between 0.5 and 4.5 V.
Failures of an accelerometer are recorded by the ECU and can be retrieved using TestBook. A special tool is required
to remove and replace a sensor in the bracket.
 

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  • ACE valve layout.JPG
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Exactly the same symptoms as mine...
ACE warning light

@2000 TD5 ES with everything on it. 69000 genuine, not off roaded, tows a caravan regularly.
Just returned from a fast visit to Kendal without the caravan (left N Kent 1330 Thurs, back 220 Fri), 700 miles in 36 hours!
On the way back, travelling as fast as limits permitted (honest ossifer), M25/M1/M6 up then back across to the A1M then down (because of the poxy M1/M6 roadworks!!!), occasionally when slowing right down (for traffic etc), the ACE warning light would come on red and bong. Each time it happened I turned the engine off for a few secs and switched on again - no lights - so continued. No changes in cornering ability or 'feel'.
Went out this morning (Sat) and checked - all levels correct, no leaks.
I've read all the posts I can find ref this light and none have said that it comes and goes with no problems....
Am I missing something?
Thanks in advance for any help/suggestions.
Dave'
 
Thanks for the link, brilliant :)

Time to begin the read... Oh and get a code reader on it - probably much quicker than my own diagnostics!

However, there was an interesting reply to the above post, 'Swap the ACE Relay with the Fog light one and see if that fixes it'.

If this relay controls fluid pressure somehow and went intermittent under temperature (we all know how high current relay contacts carbon up) it may cause the RED light too! I mention temperature as when the vehical halts after a long slog component temp will soar.

Food for thought...
 
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that relay out deffinately triggers constant amber light and locked bars ...at least that's how it's normal...the relay feeds the ECU and if the ECU is left without feed it can't trigger the red light, the amber light will stay on after self check as it doesnt get any input from the ECU..., it has nothing to do with the pressure which is mechanically delivered by the pump...you can check to remove the relay then go for a ride and IMO the amber light will be constantly on and you'll see what "Locked bars" mean...if it's duifferent then the problem might be from the ECU or the instrument pack's internal warning lamp check circuit...let's hope not

and for ACE hawkeye is more performant as it's built with the testbook T4 protocol, nanocom used to make tricks with the ACE
 
Thanks again for your advice, it's much appreciated.

Tonight I expect the RED light as I stop at the same traffic lights after a 45 min constant run, this is its 'normal' trigger. Once lit I normally just restart to remove the annoying beeps (and light) but tonight I'll avoid and chuck her around a bit and try and feel any differences (just for my own benefit).

I'll check the pump's swirling the ACE fluid, for leaks, fluid level, strange vibration (which emanates from the Valve Block and reduces if I squeeze two pipes).

Lea
 
Red light on last night - can't feel any difference at all! No leaks, plenty of swirling in header tank, an engine restart resets the light to off and it stays off.

I'm hoping this is an intermittent (heat related) pressure transducer issue, however the groaning/vibration from the Control Valve Block at 1-1.5k is still a worry!

Code read next Friday.

Lea
 
Had the codes cleared and read back (after ACE red light) when it was warmer weather:

Pressure Signal out of range
Directional Control Value fault
System temp too high

I'm convinced it's related to heat based on the red light only triggers in warm (25-30deg C) ambient and either after 30 mins regular driving in town towing the caravan, or after a 45 min run and stopping at traffic lights etc (as heat builds). The ACE red light can be reset upon engine restart and it's gone (for a while).

BTW I have been quoted 3k to replace the ACE system!!! :eek::eek::eek:

Questions for the gurus:

I know the ACE pressure sensor is on the DCV block., but where's the ACE temperature sensor located?

Does the temp sensor measure ACE fluid temperature or something else/both (DCV block?)

Has anyone stripped the DCV block and repaired?

I suspect it's a PCB solder joint somewhere in the DCV block, maybe on the solenoids based on the fact the ABS modulator (three amigos) suffers with this.

Are there any PCBs within the DCV block?


Your thoughts most welcomed.

Cheers
Lea
 
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I had problems with ace some time ago and the only event that ever gave a red light was total loss of fluid ( happened a few times) . This was based on total loss of system pressure. By your symptoms I would guess the pressure control valve is at fault. When you slow down and engine rpm reduces its not responding fast enough. Either this or your pressure relief valve is stuck open which is quite likely as this would give additional load to hydraulic circuits and resulting in high temp. All housed within modulator block which is the one under your drivers seat. Its non serviceable other than filter and solenoid coils. Sounds like you need a new block. If it turns out to be this be careful, used ones come up but its impossible to tell their condition. And they prob be full of crap and dust. Consider a new one if you want to keep ace. Maybe try to simulate the fault by keeping revs up around 3 to 4000 with vehicle stationary. Keep revs up for a minute or two then reduce to idle and see if it all kicks off.
 
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Had the codes cleared and read back (after ACE red light) when it was warmer weather:

Pressure Signal out of range
Directional Control Value fault
System temp too high

I'm convinced it's related to heat based on the red light only triggers in warm (25-30deg C) ambient and either after 30 mins regular driving in town towing the caravan, or after a 45 min run and stopping at traffic lights etc (as heat builds). The ACE red light can be reset upon engine restart and it's gone (for a while).

BTW I have been quoted 3k to replace the ACE system!!! :eek::eek::eek:

Questions for the gurus:

I know the ACE pressure sensor is on the DCV block., but where's the ACE temperature sensor located?

Does the temp sensor measure ACE fluid temperature or something else/both (DCV block?)

Has anyone stripped the DCV block and repaired?

I suspect it's a PCB solder joint somewhere in the DCV block, maybe on the solenoids based on the fact the ABS modulator (three amigos) suffers with this.

Are there any PCBs within the DCV block?


Your thoughts most welcomed.

Cheers
Lea


Hi Lea, before you do anything else or spend any money, my advice would be to get yourself an aerosol can of switch cleaner, get under the vehicle and disconnect the electrical connector at the valve block -directly under the drivers seat fastened to the chassis rail.

Very often the contacts in these connectors get dirty/corroded and need cleaning. Spray both halves of the connector, leave for a couple of mins then spray again - now connect and disconnect a few times to ensure the contacts are good, then leave connected.

Now test-drive the car.


Dave

PS £3k for removing ACE - they were wearing masks I take it? The bloody robbers. £300 is nearer the mark.
 
Hi Lea, before you do anything else or spend any money, my advice would be to get yourself an aerosol can of switch cleaner, get under the vehicle and disconnect the electrical connector at the valve block -directly under the drivers seat fastened to the chassis rail.

Very often the contacts in these connectors get dirty/corroded and need cleaning. Spray both halves of the connector, leave for a couple of mins then spray again - now connect and disconnect a few times to ensure the contacts are good, then leave connected.

Now test-drive the car.


Dave

PS £3k for removing ACE - they were wearing masks I take it? The bloody robbers. £300 is nearer the mark.

Replacing Ace,not removing !!,still strong enough:(
 
Cheers Dave, good thinking :) if the rain holds off this weekend I'll take a look at the connector an get my contact cleaner out :)
 
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