I'm working my way through a non-starting Focus that stranded itself on the hard shoulder, it died at motorway speed and now will not start.

YaY!

 

 

So armed with the wisdom of the Internet I eventually settled on a failed Instrument cluster being the root causeand on inspection did find what looked like failed solder joints on the back of the cluster.

Having resoldered the joints it remains just the same, immobilized but will crank a couple of times before de-activating the starter circuit.

I thought about downloading Forscan and seeing if there was anything to be found in its fault codes and I have a well used ELM Bluetooth unit that appears compatible with Forscan, however when I plug the ELM unit in it does not appear to show any CAN activity.

 

Does the immobiliser shut down the CAN bus ?

As there doesn't seem to be a single reference to OBD turning up in search I guess this isn't much of a topic for discussion on here.

 

The wiring diagram might stop this car meeting a HIAB, 

Back to duckduckgo it is then!

Is yours a modified ELM cable with the switch?  If not, it won't show the HS CAN modules.

No, its a standard £5.00 Bluetooth unit I use to read codes and clear them after fixing stuff.

Nothing Ford specific just the standard codes.

I have found some interesting topics on CanBus troubleshooting on here that might save the Blue Meanie from the cubing machine.

Its my daughters car and the oil change we did last month is the first time the bonnet has been opened for three years apart from topping off the washer bottle, this is not a car that has been pampered.

 

 

I’d recommend getting a proper ford specific ELM cable from tunnelrat electronics. Always works with mine, worth a try at £15.

On 4/29/2019 at 10:48 PM, GafferTape said:

Having resoldered the joints it remains just the same, immobilized but will crank a couple of times before de-activating the starter circuit.

I thought about downloading Forscan and seeing if there was anything to be found in its fault codes and I have a well used ELM Bluetooth unit that appears compatible with Forscan, however when I plug the ELM unit in it does not appear to show any CAN activity.

 

Does the immobiliser shut down the CAN bus ?

If the immobliser remains on, it should not crank at all. The PCM controls the starter relay. The odometer display will look strange, just dashes usually, and the immobiliser LED will flash quickly.

The immobiliser definitely does not disable the CAN bus, I had to use the CAN bus (via Forscan) to get the immobiliser dis-armed after I had the 2006 cluster fault.

When you try to get Forscan to connect to a car, it will first report on whether it can connect to the ELM. The first few lines of a Forscan session I had are:

(WARN) [16:35:17.428] Checking COM1...
(OK) [16:35:17.728] Connection to adapter has been established on COM1
(OK) [16:35:17.728] Adapter:  ELM327 v1.5
(OK) [16:35:17.888] Connection to vehicle has been established
(OK) [16:35:45.448] Vehicle: Ford Focus Duratorq-Turbo Diesel Common Rail Injection 1.8L 2006 ( 2003.25 MY ), VIN: WF0*********7***0
(OK) [16:35:46.279] Found module:  PCM - Powertrain Control Module
(WARN) [16:35:48.622] DTCs in PCM: U0073-E1, U2197-61, P0571-61, P1260-61, U0121-E1, U0140-E1, U0001-E1, U0155-F1, U0131-F1

So if it does not get as far as finding the ELM, then the problem is the ELM. The quality of these things varies hugely, especially wireless ones. Use a USB one if you can. The ones sold by tunnelrat have been recommended by others on this site, wired or wireless.

I was literally typing that at the very instant the reply from Daniel popped up on my screen!!

https://tunnelrat-electronics.fwscart.com/

If it cranks a bit, and the immobiliser LED is not flashing madly (it actually flashes out a code), then there is something else preventing starting. Double check the battery and heavy wiring to the starter. Then try to get Forscan working. It is the best available system outside the Ford IDS system.

 

I removed the instrument cluster and resoldered all the remaining connector pins, they looked fine but I had some spare time and now I can read from the OBD2 port so progress at least.

With Forscan I can at least see a bit more of whats going on, not a lot it would seem, these pending codes imply nothing is talking to anything else

With a test meter at the OBD port across these pins there is a reading of 61 Ohms

Pin 6 - CAN High

Pin 14 - CAN Low

15 hours ago, GafferTape said:

With a test meter at the OBD port across these pins there is a reading of 61 Ohms

The 60 / 61 ohms shows the bus is physically intact from end to end, that is ECU to IC, including the connections to the ECU & IC pcbs. But it does not test all the stubs that lead to other modules on the bus (steering, ABS etc), nor the bus transceiver chips and processors.

The full (WIndows) Forscan lists all the modules it can find, and tells you which module the DTCs are in. This can be helpful for U DTCs, knowing which module has lost communication with the Power Steering Module, etc, could narrow it down to one failed module.

There are also Self test routines in most module that can be initiated by Forscan. If there is no connection to that module, it will not even start the test.

I always record all DTCs, then clear them to see what comes back & when. Just maybe the system voltage is dropping badly when it tries to crank, and causing most of the errors. Also look carefully for any non U type DTCs. They are likely to be more directly helpful.

After further reading on here The HS-Can is presented on pins 3 and 11 at the OBD port.

This reported 60.5 ohms so looks good in a static test.

Charging the battery and will have another look when its stops raining, perhaps I'll try and find the unit test section in forscan.

 

I might knock up a low power oscillator that makes a continuous tone which varies with the resistance across the canbus, this would make connector waggling more productive.

7 minutes ago, GafferTape said:

The HS-Can is presented on pins 3 and 11 at the OBD port.

This reported 60.5 ohms so looks good in a static test.

The MS-CAN bus is on pins 3 & 11. This one goes from the IC to the BCM, via any interior electronics like restraints (belts) module & door modules. The HS-CAN bus is the engine one.

Since you had a DTC showing from the BCM, (Body Control Module, aka GEM), it was a good test to do.

I had a fiddle with the PCM diagnostics and although the pending DTCs imply nothing is talking to anything else I did manage to launch a diagnostic that sounded like it was activating idle control valves.

Is the PC based version equipped with more utilities ?

 

In regards to trouble shooting, where do I go next ?

Where is the other Canbus termination resistor ?

I would like to unplug everything from the canbus (apart from the other terminator) and try running diagnostics on each module as its re-connected to try and isolate which one is causing problems.

Being fond of spontaneous gadget purchases I might actually spring for a digital oscilloscope as well, just to see whats chattering on the canbus.

47 minutes ago, GafferTape said:

Where is the other Canbus termination resistor ?

There is one in the PCM (HS-CAN), two in the IC (HS & MS), one in the BCM (MS-CAN).

The trouble with these multi-drop buses is that it is impossible to see where signals originate, the whole bus is just one pair of wires. Disconnecting modules is one way, though the ABS is a bit hard to get at I think.

If I recall, I have seen two or three test facilities for the PCM, and probably just one each for BCM & IC, and possibly ones for EHPAS (steering) and ABS.

If the car won't start, or won't run, then the HS-CAN, or something on it, is the most likely suspect.

I disconnected the battery and charged it.

Following a battery re-connect the engine will crank but not start since the immobiliser will not disarm, so it wont run because its immobilised.

'Scope arrives tomorrow and my old Autel code reader is going to donate its OBD plug to make a breakout lead so I can see whats going on.

4 hours ago, GafferTape said:

the engine will crank but not start since the immobiliser will not disarm, so it wont run because its immobilised.

I am fairly sure my car would not crank while immobilised. It makes sense, no point in damaging the battery or starter if the wrong key is being used. The ECU controls the starter relay, so would need to be working properly to engage the starter. And the ECU is the heart of the immobiliser system. That way there is nothing that can just be by-passed or hot-wired.

The difference might be important. To disable the immobiliser needs some communication between IC and ECU over the bus. So that suggests there is at least some valid activity on the bus.

Symptoms of being immobilised include rapid flashing immobiliser LED, dashes in the odometer, and DTCs that specifically relate to immobiliser or theft. I have seen a few of those DTCs.

A low battery will cause lots of U type DTCs. If the engine turns over, it suggests some other fault, like fuel pressure, injection or low compression, is preventing it from firing up.

 

When my 'Scope didnt turn up today I put some thought into getting the Ford Ornament off my driveway by any other means.

When I realised that I had downloaded Fordsys instead of Forscan this seemed like a good time to try the software recommended so I downloaded the PC Beta version, still bluetooth but on Windows 10 instead of that Google Cobblers.

In short I ran every diag and module reset and the darn thing only started.

 

I am impressed, it might break at the next pothole but today it works.

 

To celebrate I dragged out the TurtleWax then washed and buffed one door on each side of the car just to highlight what it could look like if the owner gave a flying fog about looking after it.

10 hours ago, GafferTape said:

To celebrate I dragged out the TurtleWax then washed and buffed one door on each side of the car just to highlight what it could look like if the owner gave a flying fog about looking after it.

What is it about women and cars? My daughter's just the same. The only time it gets cleaned is when it goes in for a service.

I also wonder how they end up with so much rubbish in the car...  It seems to be a universal thing judging by the amount of memes on the subject though...  

 

 

Might have done a better job if I hadnt done it in the dark 🙂

 

 

Test drive over 50 speed humps showed no issues so in summary, resolder the Instrument cluster and reboot the car to cure its woes.

So thanks for the forum, it saved a Focus from ending up at ASM!

17 hours ago, GafferTape said:

Might have done a better job if I hadnt done it in the dark 🙂

 

 

Test drive over 50 speed humps showed no issues so in summary, resolder the Instrument cluster and reboot the car to cure its woes.

So thanks for the forum, it saved a Focus from ending up at ASM!

Good work mate, it just goes to show what determination and a bit of knowledge can achieve!