I'm getting a clearable DTC from the adaptive suspension system indicating a problem with the lateral sensor, I suspect a wiring issue as I can see the signal working with my Autoenginuity cable.

Codes C1515 & C1516

Can anyone let me know where it is.

This is what I can see with the AE tool.

 

How do you know if this is a plausible signal?

 

Lateral accelerometer is located under the bonnet near the firewall on the right side. It is in the covered area along with the ECU.

See post #4 for more info:
https://www.jaguarforums.com/forum/x...-switch-73487/



I am very curious how you get AE to connect to the adaptive damping module. I have been trying to do just that and can't seem to get the communication set up right.

 

The codes indicate a short to battery which I guess would be prevent any signal, so I am hoping I have an intermittant issue. This is supported by the observation that the fault takes some time to return after clearing.

Not conclusive evidence but I am hoping my conclusion is likely to be correct.

 

Once I put in the Jag option password and restart AE, it asks which modules you want to connect to, the first or second one on the list is the adaptive suspension unit. I click on this then selected the lateral sensor output and leteral acceleration value to monitor. It worked first time. Ill post up a couple of screen shots later.

 

The accelerometer is not connected to the battery directly but powered from the control at +5V. The signal it sends back should be proportional to acceleration in the range of 0 to 5V, so if you see +12 on either the supply or the signal line of the sensor I would be suspicious of a problem in the control itself.

 

I am also a bit dubious about the trouble code explaination, if Vbat got onto the 5 volt line anywhere the electronics would be fried and would be unrecoverable. The first thing I will do is check all the connectors.

 

It's a concern, but these things are pretty hearty and may not actually blow out with +bat applied.

Can AE show the actual voltage rather than the G equivalent?

The vertical accelerometer reads 2.5V at a stationary 1G and assuming the same scaling for the lateral one, then +12V would show as 4.8G, which is about what you are seeing.

Nominal voltage for the lateral sensor output should be 1.2V.

 

Some new observations.

First a quick drive in the car, as usual I can not tell if the adaptive damping in coming on or going off, this is the same since we got the car in March. However I don’t drive it much, probably less than 200 miles total, its normally driven by my partner.

Checked to see if the dtc had returned, it had not. I AE to monitor the 4 damper signals, the "low speed flag" and the "lateral accelerometer firm flag".

Went for a spirited drive, the two flags toggled on and off as expected with speed and fast cornering.

The 4 damper signals did not change as expected, I thought that they would all change at once, what I actually observed was the two rear ones did not change at all, stayed at zero, the two front ones went to 1 when the low speed flag went to 1, they then toggled on and off in a similar way as the "lateral accelerometer flag" toggled on and off, but were not identical.

When the sensors are monitored, the actual voltage is not displayed, just the G force, "lateral accelerometer" and "lateral acceleration" both seemed to give the same result, but I will double check this later in the week.

One odd observation is when the module is interrogated, the an "adaptive damping error" is shown on the dash. Also when I monitored "error message" it is reported as a one.

Finally I could not find the lateral accelerometer, it looked like there were just two connectors in the indicated area.

Anyway here is a screen shot showing all the sensors and parameters that can be monitored.

 

There is also an input from the brake pedal, which could explain the two fronts coming on independent of the rear, if you happen to have had the brakes applied.

The one state that you can be sure of is that all 4 are supposed to be firm when the vehicle is stationary.

What sort of values did you see from the accelerometers? Were they in that 5G range that you saw from the intermittent signal or something more realistic?

 

The pic in the top post looks like it was jumping up to 5g which is unlikely since it was me shaking the car while stationary while sitting in the driver seat.

If anyone has an actual picture of the sensor I would appreciate seeing it.

 

The lateral sensor is for the front only and it is next to the ECM under the hood. There is also a a rear vert sensor in the trunk below the fuel tank and a front vert sensor in the console behind the head unit.

 

And it isn't the easiest thing to get to as it is UNDER the ECM. The arrow in the picture points to the sensor. The bolt that holds it in is the easiest thing to see from the angle of the picture, the connector and wires come in form the side.

 

Ok, I eventually found the sensor, it is on the other side in UK cars and on the inner skin of the ecu housing rather than the outer.

Checked the connector and wiring and it looked ok from a superficial look anyway.

Also checked the connectors to the other components.

Since I started the thread I have had no further errors and there are no sensor errors being reported on AE either.

However, using AE to show the the shock activation, it seems that only the fronts are being activated and not the rears, so unless anyone has a detailed description of the system sensor values reported by AE, there is not much else I can do.

 

Perhaps it was as simple as a dirty contact and the jiggling is all that was really needed.

I still haven't been able to get AE to connect to my suspension control module but did get a confirmation from AE that there is no special setting required so my suspicion is that there's something up with my diagnostic connector.

When I do get it to work, I'll post some data from (what I think is) a properly functioning system.