Jim_Cambridge

Engine Malfunction error

Recommended Posts

Model: Focus 1.8 TDCi 2009 Mk2.5

Symptoms: When turning on ignition, warning 'Engine Malfunction', won't start. Error codes from test mode were D900 (common) and E510. I "self-diagnosed" instrument cluster fault after much reading on the web. I sent it off to a reputable company, the said they found it was faulty and could repair and send back to me next day, great I thought.

Now I've refitted it, and it I get same error. The only difference I can notice is an additional error DTC 9681, which seems to relate to transponder/key but not sure if it's really this. I tried the spare key and no difference.

I attached a code reader (a cheap one I got off ebay) and both before and after the 'repair' it could not connect and pick up the codes. It worked in the past so I think something is broken in the comms? Anyone got any thoughts or things to try? I've checked the fuses, battery seems ok, it is quite new.

My plan is to call the company on Monday to ask what fault they found, as they said it was faulty and then was repaired. But I don't know for sure it was faulty when I sent it to them.

I guess next step is call breakdown service and get it taken to Ford garage and prepare for the bill...

 

 

Share this post


Link to post
Share on other sites

Update: I have now been able to read error codes, think I didn't have ignition on before, doh...

U1900 CAN Communications Bus Fault - Receive Error

U2500 (CAN) Lack of Acknowledgement from Engine Management

 

Share this post


Link to post
Share on other sites
On 4/27/2019 at 6:42 PM, Jim_Cambridge said:

Error codes from test mode were D900 (common) and E510. I "self-diagnosed" instrument cluster fault after much reading on the web. I sent it off to a reputable company, the said they found it was faulty and could repair and send back to me next day, great I thought.

Now I've refitted it, and it I get same error. The only difference I can notice is an additional error DTC 9681,

The cluster Test mode codes can be converted to proper DTCs, see:

D1900 is U1900, and like you say is very common. Not very helpful on its own.

E510 is U2510 - Invalid security data received from powertrain ECU

9681 is B1681 - PATS Transceiver Signal is Not Received

A Ford franchised garage will not have a clue, they will just blindly follow instructions from the computer screen, replace the IC (£800+), maybe replace the ECU (£1000+), then start on the wiring looms.

ECU Testing Ltd claim to give a lifetime warranty on repairs, so defo worth contacting them. All the DTCs, with the circumstances or time / date, will help them.

The IC (cluster) is normally the prime suspect here. The transponder ring, which is around the ignition key barrel, connects to the IC, so the IC actually reads the PATS codes out of the key. It holds (I am told) copies of codes for valid keys, and is certainly part of the process for checking the validity of the key.

But the main part of the immobiliser is in the ECU. This gets the codes from the IC over the CAN bus, and also validates them. Only then will it enable any of the processes needed to start the engine.

B1681 suggests an IC internal fault. But the others (U1900, U2510 & U2500) all seem to relate to a communication failure  (HS-CAN bus) between IC & ECU. If it was a major CAN bus failure like the classic bad joint on the IC that I had, I would expect more CAN bus related error codes than that. But maybe they have all been cleared, and now only the immobiliser ones are coming back as the system gets no further than this.

The transponder ring is quite easy & cheap to replace, it does not need coding to the car at all.

A quick test on the CAN bus is the 60 ohms between the lines when de-energised. Pins 6-14 on the diagnostic connector can be used to get to the bus. This tests the bus from end to end, which is ECU (aka PCM) to IC.

Check fuses in the engine bay fuse box. F30 (3A) is a vulnerable one that powers part of the ECU.

There are two connectors low down under the trim panel just in front of the passenger door that the CAN bus passes through. (there are 3 connectors there in all), they can get corroded.

An advantage of Forscan is that it tells you which module the DTC is in. With vague communication errors, this does make a difference. Forscan is not expensive, just around £16 for the adapter, free software for Windows, and small charge for IoS or Android apps.

All diagnostic systems connect over the same HS-CAN bus to the ECU and IC as is used by the car normally, so if the bus is broken, they will not connect. That may be a clue.

Share this post


Link to post
Share on other sites

I ordered a Forscan compatible adaptor but annoyingly it hasn't turned up. I've ordered another one for delivery tomorrow.

I have tested the resistance between pins 6-14, I get 120 ohms. I understand the ECU/PCM is 120 ohms and the IC is 120 ohms so one is open circuit?

Next I disconnected the Instrument Cluster, and then I get open circuit on the pins 6-14, so I guess either faulty ECU/PCM or fault in the connections/wiring? I have checked all the wiring I can get to, such as the panel just in front of the passenger door, I took off wheel arch panel where ECU is and nothing looked amiss but I can't really check it properly. Tested the 3A fuse 30 that is fine. I plugged and unplugged all the connectors on the GEM, which I got repaired a few years ago due to water damage but no sign of water now and it's not been wet for a while anyway.

Share this post


Link to post
Share on other sites
On 4/27/2019 at 6:42 PM, Jim_Cambridge said:

Model: Focus 1.8 TDCi 2009 Mk2.5

Symptoms: When turning on ignition, warning 'Engine Malfunction', won't start. Error codes from test mode were D900 (common) and E510. I "self-diagnosed" instrument cluster fault after much reading on the web. I sent it off to a reputable company, the said they found it was faulty and could repair and send back to me next day, great I thought.

Now I've refitted it, and it I get same error. The only difference I can notice is an additional error DTC 9681, which seems to relate to transponder/key but not sure if it's really this. I tried the spare key and no difference.

I attached a code reader (a cheap one I got off ebay) and both before and after the 'repair' it could not connect and pick up the codes. It worked in the past so I think something is broken in the comms? Anyone got any thoughts or things to try? I've checked the fuses, battery seems ok, it is quite new.

My plan is to call the company on Monday to ask what fault they found, as they said it was faulty and then was repaired. But I don't know for sure it was faulty when I sent it to them.

I guess next step is call breakdown service and get it taken to Ford garage and prepare for the bill...

 

 

It sounds like the ignition system is not reading the body control unit maybe reset the power control unit as well usually £25 to £40 each to get checked -ford usually charge. £100 for a diagnosis  check

Share this post


Link to post
Share on other sites
15 hours ago, Jim_Cambridge said:

I understand the ECU/PCM is 120 ohms and the IC is 120 ohms so one is open circuit?

Next I disconnected the Instrument Cluster, and then I get open circuit on the pins 6-14, so I guess either faulty ECU/PCM or fault in the connections/wiring? I have checked all the wiring I can get to, such as the panel just in front of the passenger door,

Exactly right, 120 ohms is in each of ECU & IC, making 60 ohms if both are connected between the bus lines. With all wiring faults I always double or treble check everything, it is so easy for a fault to look like it is in one place, but actually somewhere else and it is the movement of the cables or general random disturbances that caused a change. But open circuit with no cluster is a good indicator of a broken bus. I hope it is not in the ECU, I think a connector or cable fault between them is much more likely.

The HS-CAN bus goes through two of the three connectors down under the trim in front of the passenger door. It also goes through the big connector in the engine bay fuse box. You can usually see it as the grey-red & blue-red twisted pair of wires. Pins 1 & 15 on the fuse box connector (C90). The ECU is much harder to check as it has a security bolt holding the cover on that has to be drilled or ground out. C90 is the closest point to the ECU that you can easily get to.

This pic is the best I have been able to find for C90, it seems to match up with the Focus pinout as far as I can tell.

C90.png

Share this post


Link to post
Share on other sites

thanks again for the replies. I tested the C90 connector, it's 120 ohms. Also the same pins on the fuse board side of the connector is 120 ohms, not sure if that helps. So any more thoughts?

Also I got the scanner, tried to connect with Forscan and it said it "Unable to connect to vehicle. Please make sure ignition key is ON and try again" (ignition was on!)

I checked the connector below the rear seat by drivers side passenger door and gave it a wiggle. Couldn't see anything wrong or water etc.

Share this post


Link to post
Share on other sites

So I got it working - after wiggling some cables under the steering column. Presumably it was a bad connection. Now I need to find exactly where it is so the car doesn't break down again. For anyone reading this thread at a later date, it may not be that helpful. I am still unsure whether the Instrument Cluster was actually faulty (as I was told) or not and whether I wasted around £170 getting it repaired. At least it has a lifetime guarantee!

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.