P1703 Error - Engine Or Sele Fault?

[Davo 0]

Sourced a good (used) solenoid and fitted today - warmed her up, topped up fluid, bled clutch, calibrated and checked rod length. Took her for a 20 minute run with lots of starts and stops - no leaks and normal, unremarkable shifting.

 

Second run later in the day, she dropped out of city mode on a 3rd to 4th change (first time that has ever happened) and a minute later spat out a "Sele system failure" message traveling at 60km/hr. No repeat for the next 10 minutes of driving and no hint of stalling. Hooked up MES at home and I've got the seemingly ever-present P1743 clutch sensor high error

 

.... Not feeling very hopeful I'm afraid ....

 

Ps: that LW 174 "error" was just the untuned radio station due to having the battery off :)

 

Next day: dropped out of first into neutral on the driveway / Sele failure message shifting up from 3rd to 4th (P1743 clutch sensor high error on MES)

Edited November 11, 2012 by Davo

[Smaky 73]

 

Ps: that LW 174 "error" was just the untuned radio station due to having the battery off :)

 

 

 

Yup

[Smaky 73]

Set length and calibrate ,this is possibly the sensor aswel though.

[Davo 0]

Yep, I check the length every time I calibrate (have calibrated a couple of times this weekend after the soleoid swap) but still getting the sele failure message and the clutch sensor high code, the rod length doesn't vary at all.

 

That's a new clutch sensor and replaced solenoid without any impact on the problem, and from previous work I'm certain the wiring, earths voltage etc are solid. I did find if I floor it up hill on the driveway I can force a Sele error (and annoy the neighbours with some wheel spin). Doesn't give the clutch sensor error, just the engine speed and throttle shut-off.

 

Not sure where to go next, everything seems to point to the clutch positioning - if it isn't the sensor or the solenoid then it's feeling mechanical (as in the cylinder??)

 

Actuators still on back order from Alfa I hear!! Wreckers have them from $800 here but that would be the second one in two years.....

[Smaky 73]

Read right through again,

 

It's NOT the actuator, and from thinking this over a little more I think it's time to get the gearbox off and insect it inside, also possibly replace the clutch.

[Davo 0]

After a depressing weekend thinking it through I'm thinking the same - clutch was replaced 20 months ago just before I bought it (reconditioned actuator was 6 months earlier) and has probably only done 5,000km since but something is acting up and if it isn't the actuator then clutch / gearbox is next....

 

I'll have a chat with the mechanic that did the work.....(he is a good one at least!).

 

Thanks for staying on the case with this one Smaky

[Smaky 73]

I'm suspecting the input lever loop has snapped, which effectively means new gear box as you require the centre case section and they only come as a set from the stealers... £420 here aswell

[Davo 0]

It is going to be a while before I can get the car to the mechanic so I figured I would test one small theory that the problem seems worse from cold for the first few kilometers while things warm up. Sure enough on startup I had flickering N on the display and same for gears 1,2 and 3. Random "flickering" not regular flashing to be specific (first time I have seen this...). Some strange shifting followed i.e. car in second but 4th displayed and slightly rough changes then things felt more normal after 5 minutes. I stopped and with engine off in mar had more flickering gear displays.

 

Ran a calibration to settle things down and decided it was time to to play with the MES clutch self calibration routine having read about it a fair bit researching this problem. Ran the process first go and I must say it really does smooth out the gear changes, really noticeable and certainly worth doing

 

Of course I then thrashed the car around the neighborhood for 20 minutes with zero errors and not a single flashing display, just a happy 147 doing what it should...... (not that I expect this behavior to continue....) I'll let it cool off and see if I can break it again.

[Smaky 73]

Check the connectors are tight into the back of the speedo head.

[Davo 0]

No please don't send me back to electrical troubleshooting land

 

Reseated the speedo connector (by feel - couldn't get the clocks right out - night time, first try on the 147 etc...), and getting into the spirit I hit the relays next to the battery with contact cleaner then thought about the Sele ECU in the passenger footwell so I cleaned and reseated both those connectors and the relay there.

 

40 minute / 20km thrash around the back blocks and not a hint of trouble, even with lots of stop / starts.

 

Let's see what a 1 hour session in Sydney peak hour can do tomorrow....

Edited November 14, 2012 by Davo

[classic 2]

I see you're dealing with some similar issues and faultcodes that I am,

did your car put out any other symptoms before you changed the cranksensor?

 

I also get the p0725 fault,

and in addition, the car stalls the first to-three times I'll try to start her up after the fault accurs.

(not responding to my pushing the accelleratorpedal)

[Davo 0]

Hi Classic - I had a long battle with "flashing gears" on the display and crazy gear selections a year back that ended up being due to a the 20-pin connector and some melted wiring (definitely no error codes on the Sele or engine ECU).

 

This latest round of stalling has been centred on two errors - P1743 Clutch Sensor (high signal) and P0725 Engine Speed (no signal). From what I gather the P0725 might be seconday to the P1743 (but I'm not sure). The first symptom was stalling on takeoff, then some Selespeed Failure messages and more recently I'm seeing dropping into neutral while at speed and gear numbers flashing on the display (which is making me think wiring again.....).

 

If the errors were more repeatable we would have a better chance to nail the underlying problem(s) but I find I think I have fixed something only to have it reappear two weeks later - depressing!!

[Davo 0]

Interesting day's testing: nothing to note on first startup, a couple of flashes between 4th and 2nd on the display, one Sele system failure message at speed in 3rd ( all this within the first 3 minutes) no missed changes or dropping into neutral and a perfect drive all the way to work (one hour / 25 km / stop-start most of the way) MES reported the error was P1743 clutch Sensor high.

 

The home trip produced a single "confused" flash between 3rd and 5th (it was in 3rd...) within the first kilometer and then a perfect run home.

 

Seeing as the car was well and truly at operating temp I ran a calibration and checked the rod length (28.1 as always)

 

So, what can impact the Sele performance when the engine is cold versus nice and warm? I'm thinking the above symptoms are looking more electrical than mechanical???

 

What is the bet as soon as the daughter get back into it it stalls!

 

[Smaky 73]

Interesting day's testing: nothing to note on first startup, a couple of flashes between 4th and 2nd on the display, one Sele system failure message at speed in 3rd ( all this within the first 3 minutes) no missed changes or dropping into neutral and a perfect drive all the way to work (one hour / 25 km / stop-start most of the way) MES reported the error was P1743 clutch Sensor high.

 

The home trip produced a single "confused" flash between 3rd and 5th (it was in 3rd...) within the first kilometer and then a perfect run home.

 

Seeing as the car was well and truly at operating temp I ran a calibration and checked the rod length (28.1 as always)

 

So, what can impact the Sele performance when the engine is cold versus nice and warm? I'm thinking the above symptoms are looking more electrical than mechanical???

 

What is the bet as soon as the daughter get back into it it stalls!

 

The calculated gearbox oil temp.

[Davo 0]

Well at least I've got a pattern if not a diagnosis or a fix

 

Same again this morning, gears flashing between 1st, 3rd and 5th up the driveway, a single Sele failure message in 4th and two minutes later it was struggling accelerating in 4th (like kangarooing at speed) and dropped into neutral. All good then for an hour in traffic.

 

I'm running out of new things I can do to fix this so probably time to hand it over to a professional - but I know from experience the intermittent nature of the symptoms means weeks of theories and "testing" in between multiple visits and money spent on red herrings....

 

If only the daughter could drive a manual

[Davo 0]

Just a thought - I just found out the used Sele actuator installed in the car in 2009 was from a 156JTS (no extra detail on year model etc) but apparently the mechanic had to modify the main shaft to fit into the gearbox. This is a well respected Alfa specialist mechanic so the work will have been good....

 

Any chance this could be adding to the problems in some subtle way - it never has been "comfortable" (or reliable) and might explain the rough wiring I have tripped over in the past (now fixed);

 

http://img818.images...3/dsc0051xs.jpg

Edited November 16, 2012 by Davo

[Smaky 73]

Replaced the EV0 yet?

[Davo 0]

Yep - changed the EV0 last Saturday (post 26) didn't have any effect, multiple clutch bleeds, calibrations etc since and I'm still getting P1743 errors and dropping into neutral. the worst of the symptoms disappeared after I ran the clutch self learn routine and it has been driving well with the problems apparently restricted to the first 10 minutes of driving. Makes me wonder if I should try the other clutch setup routines on MES?

 

The strange thing is that I have suddenly seen some "confused" gear number flashing on all gears, again only for the first 10 minutes until the car is warmed up. This screams bad wiring connections or sensors to me so I have been contact cleaning everything in sight.....

 

The picture above is on the ECU side of the 20 pin connector and makes me worry about the state of the wiring looms back to the various ECUs involved. Note the black shielded wire that is hacked up - my guess is that is the clutch speed sensor wiring and I can't imagine how it would be in this state on the engine side of the connector???

[Davo 0]

OK now is when I REALLY confuse things! I was going to swap the EV0 back out to the original plus check over the wiring today.

 

First surprise was the Sele failure message from yesterday was in fact a P1742 error - gear selector sensor reading high this time. Makes me think wiring seeing as it is the first time for this error and fits with the new gear number confusion.

 

Second surprise was I had difficulty removing the EV0 solenoid- jammed pretty tight but with a bit of effort it came free and the cause was the o-ring that seals the solenoid body to the actuator was in pieces and jammed into all sorts of strange places.... I have no idea why there were no fluid leaks - or how it functioned! I grabbed the nearest o-ring that was close to the right size and screwed it back in very carefully. Primed the clutch a few times, calibrated and tested and all seems OK, no leaks or gear flashes during a short test.

 

More testing.....

[Davo 0]

Well "something" has changed - I noticed yesterday afternoon that the pump didn't kick in when I opened the door. Then this morning after an 18 hour period again no pump. Great I thought, the door switch or pump has died

 

But no, turned the key to mar and the pump kicked in for only 2 seconds rather than the usual 10 or so - could it possibly hold pressure that well?? I have never had any fluid leak prior but perhaps the pressure was equalizing somehow due to a faulty EV0? Anyway just conjecture until I get a chance to hook MES up and see what the pressures are doing...

 

Ps; perfect test drive this morning apart from a single drop into neutral coasting along in 4th or 5th . I'll drive it to work all week and see what happens.

[Davo 0]

Still no pump on opening door - pump activity during shifting on mar is the same (every 2 shifts).

 

Hooked up MES and set it up for hydraulic pressure + clutch travel (so you can see where it shifts) and went for a drive;

 

I had a few "flashing gears" in third and then a drop into neutral - saw this (green circle is where the drop into neutral happened);

 

 

Get a load of those hydraulic spikes - can't be "real" surely?? - sat watching for more spikes, engine running in neutral;

 

 

Took off again, saw no gear flashing but then got a sele failure message + drop into neutral saw this (green circle was the error);

 

 

And now this seems to be the error of choice - P1742 high signal - gear selection (not clutch position...)

 

hopefully pictures are worth more than my words!!!

[AFLA 4]

Hi Davo,

 

I am now getting the same symptoms as you are now including the P1742 error as well as at least one time the pump did not prime on door open.

 

Still need to verify the actual values pressure values.

 

I do hope the answer is as simple as a Potentiometer, Accumulator or Pump Motor Brushes which I can do alone...

 

 

 

 

Tuval

[Davo 0]

From what I gather the pressure spikes are just artifacts from the sampling time with the graph function on MES. The pump is working fine and it is taking over 7 minutes between primes sitting in mar so I doubt I have a pressure problem.

 

Given the number of different errors that are popping up and the return of "flashing gear syndrome" my best guess is the wiring playing up again. I had first, neutral etc flashing in mar this evening and it stopped as soon as I gave the harness around the 20 pin plug a good flex. The guy that supplied the EV0 valve probably has the complete electrical harness, might be an idea to get that off him and at least try it out?

 

Dodgy electrical connection would give the high sensor signals - assuming "high" = increased resistance?

[Smaky 73]

Those graphs would be pushing me towards a faulty accumulator now, plus the mention of the pump not running will be yet another fault, so this is the point were you need to decide on the options, my personal choice would be to replace the accumulator and replace the brushes in the pump motor as per the guide I've posted.

[AFLA 4]

Hi Davo,

 

I can't of course offer any help as Smaky's. but - I was able to sort out my p1742 issue (see my other thread on Selespeed jumping gears in same sub forum).

 

I was able to cure it (at least temporarily as Smaky said) by spraying it liberally with elec contact spray till it was clean enough - I think that some of the potentiometer internal mechanism is exposed and this enables cleaning/flushing it to a degree (aside from cleaning the contact itself by unplugging it) - of course I would be happier to take it off, clean it properly and put it back again - but I don't have a lift and this is how far I was able to master at this point.

 

It has now been 4 days and some 300 Miles...

 

HTH

Edited December 4, 2012 by AFLA