On Rose's road to recovery, there are a few warning signals which I have yet to tackle, and would need some advice.



The auto-transmission warning light I have dealt with by removing the light bulb from the instrument cluster, because I have replaced the auto gearbox with manual, but I have no idea of the Traction Control, Anti-Lock and Airbag lights, and I don't have any code readers.

 

Try my diagnostic process for Air Bag issues

https://www.jaguarforums.com/forum/x...ostics-112470/

 

The traction control and anti lock lights are likely connected, as the two systems share common hardware. The rear wheel speed sensors provide input in the form of speed signals, and the ABS Ecu, where all the brake pipes are plumbed to under the bonnet, does the processing of the data.
Check your rear wheel sensors first, then look for the thread on here about the known fault which can develop in the ABS Ecu due to a dry solder issue.
As a left field suggestion, I used to get the traction and ABS lights on every time I had a rear seat passenger. Turned out the rear seat springs bore down on the LHS wheel speed sensor connector, and broke the connection when someone sat in the seat! One of the easier fixes.....

 

Thank you b1mcp and countyjag for the very useful info. I shall work with my mechanic to get these sorted.

 

Hi Qvhk,

As countyjag mentioned, there are a number of possible causes of the ABS/Traction Control warning lamps, and the fastest way to diagnose them will be to scan for stored Diagnostic Trouble Codes (DTCs). If you have a smart phone, a very inexpensive and effective solution is an ELM327 Bluetooth OBDII interface device (about USD $10 on eBay) paired with the Torque Pro app (USD $5 for Android - I'm not sure about iOS). Together, these will give you a very powerful OBDII scanner on your phone.

Sometimes the problem is just a dirty wheel speed sensor that has been fouled by metallic particles in the brake dust. But in your case, the problem could be related to your transmission conversion, since the automatic Transmission Control Module and Engine Control Module can trigger faults related to the vehicle speed signal, which comes from the ABS/DSC Module. The ECM and TCM use that signal to manage smooth gear shifts, so it seems possible that your ECM, or TCM if still connected, might be unhappy due to the modifications you've made.

The fastest way to narrow down the diagnosis will be to scan the codes.

Please keep us informed!

Cheers,

Don

 

Thanks for the advice on acquiring inexpensive scanning device and apps. My mechanic said that he did a scan before but the device he used was probably intended for newer models; as some data did not show up. I just did a quick search in this forums and understood that 1995 Jaguars might be the odd siblings - there is no lack of eBay listings of ELM327 OBDII devices for iPhone, but some clearly state that on Jaguars they would cars from 1996 only...

 

The ELM327/Torque set up works fine on 1995 cars (well it does on mine at least - registered Oct 1994).

However, to manage your expectations, that set up will only be able to read engine management codes (P Codes) and data. To access codes/data from other modules (e.g. ABS) you would need to move up a level of sophistication and cost.

 

I have heard about BlueDriver and ELM327 which will work on my iPhone. I shall try to start from ELM327 first, as it is one tenth of the price of BlueDriver and very popular with DIYers as well as professionals.

 

Got the ELM327 scanner off eBay that works on iPhone. However, it or the Apps that goes with it does not read ABS and airbag codes. The first scan only produced codes in relation to the auto-gearbox which are not relevant now that Rose has a manual gearbox instead; no other codes found.


Am waiting for another scanner to detect and investigate other codes.

 

Hi Qvhk,

Can you provide a link to the ELM327 you purchased that works with iPhone? I've been wanting to get a couple for my kids so they can at least scan for generic powertrain codes with their iPhones. Most of the software packages I've seen for iPhone are more expensive than a basic hardware OBDII scanner.

Thanks,

Don

 

Here is the link from which I bought the ELM327 scanner.
Mini ELM327 Wi-Fi OBD2 OBDII WiFi For iPhone Car Diagnostic Interface Scanner | eBay
It comes with a CD software for the PC. Inside the package is a note saying that the scanner needs to work with Apps: Torque (Android) or DashCommand (iPhone). The latter is available for download for US$9.90. I didn't buy DashCommand but use a free App called EOBD-Facile.
There are also many similar eBay listings claiming that their scanners will work on both iPhone and Android devices.

 

Here is an update on scanners' findings on the dash warnings. I bought an ELM327 but it does not read O2, ABS and Airbag. The fault codes detected are all gearbox related, as the scanner rightly found that the auto gearbox system is not responding . Was waiting for the BlueDriver scanner to arrive, but eventually cancelled the order as the eBayer failed to send it even after a week. Purchased iCarsoft i930 after doing some research (mixed views, I know, but only the i930 covered old XJ as far back as 1994) - my primary aim is to verify and investigate the ABS, Traction Control and Airbag warning signs on the dash. The i930 arrived after 5 days, but alas, it does not read anything - the message that pops up is "Failure to communicate with the ECU". I tried it on my 2005 X350 and got the same message, so I can't say I wasn't forewarned of the iCarsoft capability. The ELM327 performs better on the X350, correctly diagnosing the O2s being lean on both Bank 1 and 2 after the engine amber light and the message "Restricted Performance" message emerged on the dash.

There is a very long thread in the X350 platform on this forum about OBD II scanners, which I have to do more research and try my luck on scanning my XJR, but I am not too bothered with the dash warnings, as she runs fine and stops well meanwhile.

 

I apologise if I am stating the obvious, but will the transmission warning light not now be on for all time until one of the following occurs?;
-A manual gearbox ecu is fitted, or
- a replacement automatic gearbox is fitted, or
- a way is found of mimicing all automatic gearbox sensor signals, or
- the bulb is removed.
Despite the attraction of the last mentioned remedy, even then the car will still "think" it is an automatic, and if the sensor inputs are not as it is expecting, will attempt to illuminate the warning light, and more troublingly, adopt "limp home " restricted performance mode

 

Rose is already running on a special ECU remapped by Andy to complement the conversion of the transmission from auto to manual. Why Rose still "thinks" she is born auto may have to do with the hardware remaining intact, like the auto transmission ECU, wiring/harness, the light bulbs on the instrument cluster, etc. I may have to remove them altogether later. The engine and manual gearbox are working very well together - running as if it were born manual. It pulls like a train and can cruise comfortably at low engine speed. "Limp mode" has never occurred since the conversion.

 

Today, I finally found a local workshop that has a professional scanner (Autologic Bluebox) for the Jaguar series. The codes found are as shown in the screen shots below.






The advice given to me was to replace the ABS Control Module and the Airbag Module first, as the various codes might have arisen from the modules themselves. I would give this a try, as my other mechanic has cleaned all the brakes and ABS sensors, replaced the brake discs, brake hoses, brakes pads (with EBC Red Stuff), and overhauled the front and rear calipers with repair kits (pistons, piston seals, etc.), but the ABS and Traction Control lights remain lit up. As for the airbag, I was advised that airbag sensors rarely fail so the prime suspect is the control module. Hmm......the ABS Control and Airbag Control Modules are expensive items...... I shall see if getting good used one might take care of the warning signals.

 

I was referring to the "Gearbox electronic control unit" to give it its proper name, rather than the main ECU. Im not sure which one Andy remapped for you, but the gearbox one will probably need changed too.
The airbag control modules are common with various Ford vehicles, and indeed the module is unusual on the X300 in that it is actually branded FoMoCo. They were plentiful on ebay when I last looked, and inexpensive.
For what it is worth, I wouldnt be in such a hurry to dismiss the impact sensor short circuit, which the diagnostic is reporting. I have replaced three this year on different vehicles, admittedly not Jaguars, and in each case the diagnostic was 100% correct. Also not expensive second hand.

 

I agree with countyjag that the shorted Impact Sensor should be addressed. It is likely that the shorted sensor was the cause of the internal fuse blowing (a safety measure built in to the Air Bag system to prevent unwanted deployment).

So if you just replace the module without checking the sensor then it will likely blow the fuse in the new unit.

 

countyjag, Andy remapped my engine ECU for the auto-manual conversion; it also takes care of the timing advance which otherwise requires the "Andy's Timing bracket". I do not know whether manual cars also have the transmission ECU as the auto version or will have the manual version, but I guess this is largely a hardware issue as indicated above. I would try to remove the original transmission ECU for the auto gearbox one day and see what might happen. As of now, as the car runs fine I would leave it for the time being. I would also take your advice to replace the impact sensors anyway.

b1mcp, I would also take your advice to replace the thermal fuse or the entire airbag control unit after replacing the impact sensors.

The earlier advice I received was from a local Jaguar specialist workshop - he suspected that DTC 51 might suggest airbag having been deployed before. However, it is always good to get a second opinion from here where there is a much larger sample population and proven solutions. Used parts are abundantly available so I'll see if I shall be lucky.

 

Code 51 could be caused by an Air Bag deployment. I was suggesting that you check the Impact Sensor, not necessarily replace it, before installing a new module. The procedure to test the sensor is covered in the document I provided a link to in post #2.

The Thermal fuse in the control unit is not replaceable.

 

Thanks for the clarifications. The matter is sort of out of my depth, but anyhow I shall find some good used sensors and module, and see if the codes can be cleared. The last thing I wish to see is accidentally triggering the airbag, so I would let the guy with the professional scanner replace them and conduct post-installation checks.