Electrical Issue

[Dex90]

Hi All,

I've been working on a project Clio 172 for about a year now. bought the car as a non-runner, replaced engine,clutch,fluids etc. I didn't buy the car having ever seen it run. I've come back to it this year, with the nice weather, to try and get it running and finally get it off my driveway!

problem I'm having is an issue with starting. putting the key in the ignition and into position 1 all the lights light up and then all turn off apart from the electrical fault light. having scoured the forum I've tried most of the suggestions I can find. I've checked all engine bay earths , pics attached, I haven't checked any internal earths as I couldn't find out where they were. I've changed the crankshaft position sensor, one of the most common faults apparently, which didn't help. I pulled the UCH as I heard that that can throw an electrical fault but looks absolutely fine with no water damage.



putting the key into position 3 the car tries to start , starter motor fires, but no spark, suggesting a good engine/transmission earth? the fuel pump is priming.

last year i managed to get the car started by jumping the engine management relay with a piece of wire. I don't know why I thought to try this. putting the key into position 1 all lights went out and the car fired up without issue every time,so I'm positive there is nothing wrong with the ht leads,coil pack or throttle body. i assumed the relay switch was dead so i bought a new one and installed but that didn't resolve the problem. this year the same trick does not work and doesn't remove the electrical fault light.

i thought to have a quick look at the wiring loom directly related to the engine management relay so i've unwrapped some of the electrical tape to have a quick look but what I've seen so far looks OK, nothing green electrical gremlins that I could see.


i recently bought a clip clone off ebay, wasn't cheap to me though! installed on my laptop and plugged it into the clio to try and get the reason for the electrical fault light. unfortunately I've just had issue after issue with it and I'm not sure if its the cheap clone /software/laptop or an issue with the wiring tripping the connection in some way but it keeps disconnecting . I managed to do a fault test of all computers and it came back with a fault on all modules. I went into the throttle and could see the position sensor had a figure and moved with the movement of the throttle. however it disconnected shortly after. re-running the test on all computers i tried moving the throttle and it instantly disconnected. this happened 3 times in a row so I'm not sure if this is the cheap clip or an issue with maybe an bad internal earth causing the interface to trip? testing a little later 3 computers moved from faulty to non-faulty.

so I'm out of ideas. any suggestions very welcome.

 

[bloke]

it's a power issue, broken wire, earth not switching, relay etc...

 

[Dex90]

ok will test all relays and then I'm not sure really. can anyone point out/ have diagrams of all the earths that I haven't mentioned in my first post? 2 near slam panel, one from transmission to chassis and one above transmission on engine ? anyone have diagram for throttle position sensor? I thought I would get this with clip but doesn't appear to contain diagrams.

apart from that I might try a new/used(known to be working) engine loom .

 

[Dex90]

Hi All,

thought i would update in case this helps anyone. I bought a used full loom on ebay(£35). removed most of the loom, the bit that goes inside the car, and just tried replacing the main engine loom. 6 hours later no electrical fault light anymore! the "serv" light is on but that is due to the rain sensor, when i clear the fault through clip the serv light goes out so i have no errors on my dashboard with only the attached faults.



The car will still not try and start however so I'm going to look into the starter motor.

The throttle body now makes a loud buzzing noise and a click when the key is switched from position 2 to 0, this is the throttle body valve opening a small bit and closing again quickly. i think this is normal though. however I did not have this previously with the old loom so I'll look into the old wiring for the throttle body and see If I can find where the problem was for anyone who may be interested.

 

[Dex90]

spent a little more time on the car this evening and managed to get the starter to fire. after finding a decent wiring diagram for starting and charging i found that the wire marked "pink" is the issue, this goes to the multitimer, uch? my wire wasn't pink however it was brown. i gave this wire an earth and the starter fired up first time. i have a question however the 2nd diagram which shows the pink wire goes to pin 14 on the multitimer, what does it do at that point does the multitimer switch the earth or does it just use the multitimer earth(E5)?

 

[Dex90]

oh i also managed to fix the serv light. there was a fuse that had blown for the rain sensor, so no more dashboard lights!

 

[Stay Puft]

Well done mate!

 

[Dex90]

cheers matey. can anyone clarify what happens at pin 14 on the multitimer? is it a switched earth or just uses the multitimer earth (e5)?

 

[Dex90]

so i spent a little more time on the car this evening. the wire from the relay has continuity to pin 14 on the uch but obviously it's not giving an earth. I'm stuck now, I think it's a UCH problem but not sure. anyone else experienced this?

 

[barnesautos]

P201 40 pin is where your looking at ?

Says pin 14 is starter output .

A little vaige , but clearly it's an earth [emoji290].
The power from the ignition switch travels from there all the way to the starter relay me thinks . So somehow either the multi timer unit switches that Earth [emoji290] when you turn the key as the starter circuit may poss feed the timer unit also .

 

[Dex90]

i'm looking at pin 14 on 201 yes
it has continuity to wire 2 on the "starting and charging" diagram i posted earlier.
if i give wire 2 on the "starting and charging" diagram an earth straight to the battery the car fires up straight away without issue.
so i'm at a loss at what to look at with regards to the multi timer as I cannot find any wiring diagrams for it.
can i ask where you got that diagram from?

 

[Dex90]

my multitimer model is UCH-HG if it helps at all.

 

[Dex90]

thought i would just update this thread to say the car is now working, although has a very lumpy idle for me to look into! I sent the UCH off for repair to dieselpumprepair.com as I could tell that pin 14 was not getting an earth so much be a fault with UCH, they were very helpful over the phone and fixed the earthing issue. i received UCH yesterday, plugged in and the car fired up although i have the electrical fault light again so I've got the fun of looking into that again.

 

[Chambers_RS]

I've got this issue, I have no spark or fuel pump prime tho:sob:

 

[Dex90]

if you jump fuel pump relay with a piece of wire does it send fuel to rail?

 

[Chambers_RS]

if you jump fuel pump relay with a piece of wire does it send fuel to rail?

Not sure yet lol
What pins need bridging?

 

[Dex90]

just a quick update. i reset all of the stored faults with clip and electrical fault light has disappeared.
faults stored were:
DF057 - Upstream oxygen sensor circuit
DF125 - Pedal potentionmeter circuit track 1
DF129 - Pedal potentionmeter circuit
DF019 - Dipped healights information circuit
DF067 - Decoder Connection

I think this may have been due to temp ecu/uch i was using and switched over to my original ecu and fixed uch now. i ran the car for 10 mins on driveway, was idling at 4000 rpm! checked and all vacuum hoses are on and checked fault codes stored again. following codes came up:
DF125 - Pedal potentionmeter circuit track 1
DF128 - Vehicle speed not available.

didn't have much time to investigate into wiring for pedal so have ordered a second hand one on ebay which should arrive in a couple of days and a second hand throttle body, just in-case.

does anyone know if the vehicle speed is talking about speed sensor in transmission or crank sensor? i would guess speed sensor.

Not sure yet lol
What pins need bridging?

its the big relay in the engine bay closest to the wheel arch, usually brown, one in middle. pull it out and jump the two pins in the middle i think, you should hear it either turn on or you can pull the clip to the rail to see it pumping fuel. if that works then you need to look into the wires sending signal to relay as i think the clio will send fuel on crank but not spark if an immobiliser issue? do you have electrical fault light? may be worth getting it scanned with clip if this it the case. i can't help with getting wiring diagrams unfortunately! it's my biggest enemy

 

[bloke]

Just to confirm when you say electrical fault light you do mean the yellow box with a zig zag line in it?

 

[Dex90]

Just to confirm when you say electrical fault light you do mean the yellow box with a zig zag line in it?

that's the one

 

[Dex90]

hey all , thought i would update with the latest and get some advice!
fitted used throttle pedal, no joy! still idling at 2000rpm+ . turning the car off and on eventually the car would idle at 800rpm, weird. reset all fault codes and let it run for 10 mins, fault codes that came back up were:

• DF125 - Pedal potentionmeter circuit track 1

and nothing else, which is weird because i just changed the pedal. advert said it was working fully so got a feeling it's something to do with communication between throttle pedal and body.

just replace throttle body tonight, with an apparently known working one, reset fault codes and turned car on. idled at 800rpm. restarted car and it went back up to 2000. couple of restart again and idling at 800rpm, although very roughly. funnily the car will idle at 800rpm when the electrical fault light is on.
fault codes logged with replaced throttle body:

• DF125 - Pedal potentionmeter circuit track 1
• DF254 - Motorised Throttle Control 2.Def (motorised throttle automatic control fault)

more faults then last time, maybe a bad throttle body i've replaced with or a fault that was there before but not displayed with previous throttle body?
i checked out the "list of parameters" for injection while car was idling high and normally, was a difficult task because my clip disconnects every 5 seconds when reading live data.

noteable differences were:

• manifold pressure increase by 100 mbar, i would expect this with higher rpm
• idle regulation valve opening increase by 13% (31%) with higher rpm. not sure if this is normal?
• idle regulation integral correction increase by 9(19) with higher rpm. not sure if normal
• ignition advance 20 degrees crk higher (33) at higher rpm
• average knock signal 4(34) lower at higher rpm
• engine torque -2 nm?
• injection duration 2.4ms at higher rpm , 2.84ms at lower rpm
• downstream oxygen sensor 200 higher (760MV) at higher rpm
• upstream oxygen sensor is all over the place from 68mv to 760mv, is this normal? downstream doesn't change at all
• canister bleed solenoid valve 14% at higher rpm , 0% on low rpm

 

[Dex90]

it's been a while since i posted but I have sorted my electrical fault now so thought i would update my thread with a conclusion.
focusing on the pedal potentionmeter circuit track 1 fault recorded i decided to test every possible wire between the pedal wires and the throttle body. i tested , with a long piece of wire continuity, voltage and resistance from the pedal connector (6 wires) to the engine bay fusebox white block connector.

• the 6 wires surrounded in blue plastic in the white connector block in engine bay fusebox all related to the throttle pedal connector. all wires read 12V with little to no resistance and therefore continuity was there.
• i then tested the 6 wires in the white block connector to ecu connector for same readings. all ok.
• ecu connector to throttle body connector . all ok

i was pretty confident there wasn't a problem with the wiring , without a proper scope i couldn't be 100% sure. i've already replaced the throttle pedal and that didn't resolve the problem so the only other thing I thought it could be was the ECU. i really didn't want this to be the case so I thought I would buy another second hand throttle pedal as they are relatively cheap.

throttle pedal arrived, fitted and the electrical fault light has dissapeared. turning off and starting multiple times the car ran at 800rpm, although still quite lumpy. looks like i was sold a faulty throttle pedal !

couple bits left to finish on the car and then i'll be selling on shortly to do another one!