Citroen DS3 Service light

[MarcoDS3]

I've asked above for the VIN (please post your VIN in full without spaces - it will be automatically masked from public view after submitting your post & will only be visible to staff), as I can't help relate the codes to the specific engine ECU without it.

Sorry, it’s VF7**************[VIN obfuscated, can be read by forum staff]

[GiveMeABreak]

Here you go, took me a while being the holidays.

Fault Code:	P2603
Description of Fault:	(Electric) turbo additional coolant pump control fault: Open circuit. Open circuit on the power stage of the electric coolant pump for cooling the turbocharger for more than 0,5 seconds. Conditions of activation of the diagnostics The following conditions have to be met: - Engine management ECU in main triggering phase - Battery voltage between 9 and 15 V - engine running - Power relay jammed for more than 2 seconds
Conditions for Fault to clear:	No fault codes found : P2600 - P2601 - P2603 (For 1 second)
Downgrade Modes whilst Fault is active:	-
Symptoms:	Engine overheating
Suspect Areas:	Engine ECU Electrical harness

Fault Code:	P0139
Description of Fault:	Downstream oxygen sensor signal fault: Coherence. Voltage downstream oxygen sensor above 0,2V (For more than 0,2 s) (In injection cut-off, the engine ECU checks that the information from the downstream oxygen sensor is "richness low"). Conditions of activation of the diagnostics The following conditions have to be met: - Engine management ECU in main triggering phase - Battery voltage more than 11 V - Downstream oxygen sensor heated up and available - engine running - Injection cut-off for more than 10 seconds
Conditions for Fault to clear:	Downstream oxygen sensor voltage lower than or higher than the chosen value (For less than 10 seconds) ; Downstream oxygen sensor voltage lower than 0,2 V (For more than 0,2 s)
Downgrade Modes whilst Fault is active:	Transition to open loop of the downstream regulation. No purging of the catalytic converter
Symptoms:	Emissions outside the norms
Suspect Areas:	Downstream oxygen sensor

Fault Code:	P0054
Description of Fault:	Downstream oxygen sensor resistance fault : Resistance too high. Resistance internal to the downstream sensor is too great (For more than 6 s). Conditions of activation of the diagnostics The following conditions have to be met: - Engine management ECU in main triggering phase - Temperature of the gases at the downstream sensor between 200 and 599°C - Engine off for more than 2 minutes - Inlet temperature higher than -6,75 °C - Voltage between 10,7 and 16,1 V - Engine running - No cutting of injection
Conditions for Fault to clear:	Resistance internal to the downstream oxygen sensor less than the maximum threshold (For more than 25,5 s)
Downgrade Modes whilst Fault is active:	Transition to open loop of the downstream regulation (Deactivation of the proportional part) No purging of the catalytic converter Detection of catalytic converter empty or full based on the oxygen storage capacity modelled to the place measured
Symptoms:	Emissions outside the norms
Suspect Areas:	Downstream oxygen sensor Electrical harness

Fault Code:	P0140
Description of Fault:	Downstream oxygen sensor signal fault: Coherence. Possibility 1: Non-plausibility of the signal from the downstream oxygen sensor (no activity) Possibility 2: Downstream oxygen sensor voltage between 0,5 and 0,35 V (After 10 minutes) Possibility 3: Internal resistance of the oxygen sensor above 40 000 ohms ; Temperature of the exhaust gas higher than 600 °C. Conditions of activation of the diagnostics The following conditions have to be met: - Engine management ECU in main triggering phase - Battery voltage more than 11 V - Temperature of the exhaust gases between 25 °C and 800 °C - engine running - Downstream oxygen sensor ready
Conditions for Fault to clear:	At least one of the following conditions must be fulfilled: - Downstream oxygen sensor voltage lower than 1,25 V (For 5 seconds) - Sensor voltage higher than -1 V for 0,1 seconds with downstream regulation activated - After a period of 10 s the voltage pitch of the sensor is monitored following each cut-off of the heating - If over the period of 0.040 s the pitch does not exceed the threshold of 2 V, the heating fault is temporarily removed - The malfunction is cleared after 6 checks showing no faults with sensor voltage outside the range of 0,5 - 0,35 V for 10 min or internal resistance of the sensor less than 1000 Ohms
Downgrade Modes whilst Fault is active:	Transition to open loop of the downstream regulation Deactivation of purging of the catalytic converter Deactivation of the detection of excess engine speed in changing gears
Symptoms:	Emissions outside the norms
Suspect Areas:	Downstream oxygen sensor Electrical harness

Fault Code:	P0313
Description of Fault:	Combustion misfiring detected during a low fuel level period fault: Not characterised. Suspicion of lack of fuel in the tank. Conditions of activation of the diagnostics The following conditions have to be met: - Engine management ECU in main triggering phase (For more than 1 s) - The "fuel level" information received from the CAN is valid - Fuel level low
Conditions for Fault to clear:	10 s after refilling the tank
Downgrade Modes whilst Fault is active:	-
Symptoms:	-
Suspect Areas:	Fuel gauge Fuel level indicator on the instrument panel Fuel level Electrical harnesses

Fault Code:	P0132
Description of Fault:	Upstream oxygen sensor signal fault: Short circuit to positive. Short circuit to positive on the upstream oxygen sensor: Voltage higher than 1,1 V for more than 5 s. Conditions of activation of the diagnostics The following conditions have to be met: - Battery voltage more than 11 V - engine running - Temperature of the exhaust gas higher than 600 °C - Dew point reached - Heating of the upstream oxygen sensor active - Heating power of the upstream oxygen sensor higher than 0,2 (For more than 10 s)
Conditions for Fault to clear:	Possibility 1 - No fault codes found : P0131 - P0132 - P0133 - P0134 - Voltage of the upstream oxygen sensor between 0,6 and 1,1 V or lower than 0,4 V for more than 1 s Possibility 2 - No fault codes found P0131 - P0132 - P0133 - P0134 - If the upstream oxygen sensor has reached the dew point, the heating is activated and the heating power is above 0,2 for more than 10 s and 6 cycles with the dew point reached
Downgrade Modes whilst Fault is active:	Deactivation of the richness regulation Deactivation of purging of the catalytic converter Deactivation of the canister purge function
Symptoms:	Unstable idling Emissions outside the norms
Suspect Areas:	Upstream oxygen sensor Electrical harness

Fault Code:	P0113
Description of Fault:	Inlet air temperature sensor signal fault : Open circuit or short circuit to the plus. Detection of a short circuit to positive or of an open circuit on the inlet air temperature sensor. The inlet air temperature remains below -39,8 °C (For at least 0,5s). Conditions of activation of the diagnostics Engine management ECU in main triggering phase
Conditions for Fault to clear:	Temperature between -39,8°C and 132,8°C (For more than 0,5 s)
Downgrade Modes whilst Fault is active:	Deactivation of the richness regulation Knock protection angle High pressure starts deactivated
Symptoms:	-
Suspect Areas:	Inlet air temperature sensor

Fault Code:	P0299
Description of Fault:	Turbocharging pressure regulation fault : Turbo pressure too low. Turbo pressure too low: Turbo regulation at the minimum limit; The difference between the reference turbo pressure and the actual pressure falls below the threshold of - 0,1 bars or - 0,12 bars if there is an error in the camshaft dephasing system. No confirmation time. Conditions of activation of the diagnostics The following conditions have to be met: - Engine management ECU in main triggering phase - Turbocharger pressure regulation(Active) - Atmospheric pressure higher than 0,8 bars - Engine speed above a threshold dependent on atmospheric pressure - Turbo pressure valid - No power step error - Extra delay dependent on the engine speed after these conditions are active
Conditions for Fault to clear:	After engine restart (If the difference between the reference turbo pressure and the actual pressure exceeds the threshold of - 0,1 bars or - 0,12 bars if there is an error in the camshaft dephasing system)
Downgrade Modes whilst Fault is active:	Deactivation of the turbocharger regulation A serious reduction of load is applied in order to imitate the behaviour of a normally-aspirated engine The "overboost" function is deactivated
Symptoms:	Lack of power
Suspect Areas:	Turbocharger pressure regulation electrovalve Turbocharger discharge electrovalve Inlet manifold Vacuum pump Vacuum duct for the diaphragm of the turbo pressure regulation electrovalve

[MarcoDS3]

Brilliant. Thanks mate. Much appreciated. I’ll check these things out

[MarcoDS3]

Just reading through all the info here, could it just be some of the electrical connectors are fitted correctly do you reckon? I’ve just had the plastic coolant pipe between the water pump and the thermostat replaced so they had to whip the battery out and unplug a few connectors around that area to remove the thermostat. It’s since that moment that my car’s been in limp mode. It could be a coincidence but definitely seems a possibility maybe?

[GiveMeABreak]

These things to often happen after the 'monkeys' have been at it - if it's not connectors left unconnected, or some other damage.... it won't be the first time we've heard of this. You may have water that has got into some of the sockets.

So yes have a good look, trace back the work and check every connector is secure and that the pins aren't damaged. Especially near the battery and engine ECU as this is where all the engine system sensors will come back to.

[MarcoDS3]

I will do mate. Thanks again for taking time out of you day to get all that info for me. I really do appreciate it!

[GiveMeABreak]

No worries.

[MarcoDS3]

So I had a good look at all the connectors that I could get to and the only issue that I could find was on one of the connectors to the ECU. Cannot for the life of me work out how someone managed to get what looks like oil on there! I cleaned it up as best I could but it hasn’t fixed the issue worse luck.

My next plan is to change the inlet air temp sensor to see if that is the root of the problem. Luckily my boy has exactly the same car so I can try his before I order a new one. Only I’m worried about is that, if my car has a wider electrical problem, do I risk damaging his sensor if I whack it on my car?

[gwest]

Marco, I take it that the connector is for your engine ECU? One way for oil to appear at the connector is if it has migrated by capillary action from a leaking sensor/ control unit on the engine. Oil pump solenoids are one suspect, but it could be many. That said, if you have cleaned the contacts then you would think you would have a temporary reprieve.

[GiveMeABreak]

Use lots of electrical contact cleaner to clean as best you cam.

Make sure the sensor your are thinking of swapping over is the exact same part. It should be if it is from the exact same model and engine, but be advised that it may take some time for the engine ECU to recognise and adjust new values for the sensor, so clear the fault code and take it for a spin.

[MarcoDS3]

Marco, I take it that the connector is for your engine ECU? One way for oil to appear at the connector is if it has migrated by capillary action from a leaking sensor/ control unit on the engine. Oil pump solenoids are one suspect, but it could be many. That said, if you have cleaned the contacts then you would think you would have a temporary reprieve.

Yea it’s the middle one for the ECU. I’ll check it periodically to see if the oil reappears. Thanks mate

[MarcoDS3]

Use lots of electrical contact cleaner to clean as best you cam.

Make sure the sensor your are thinking of swapping over is the exact same part. It should be if it is from the exact same model and engine, but be advised that it may take some time for the engine ECU to recognise and adjust new values for the sensor, so clear the fault code and take it for a spin.

Yea I think I’ll give it another good dousing in electrical cleaner just in case. I’ll double check the part numbers on the two sensors just to be sure before I try his. Thanks again mate

[MarcoDS3]

So, I’ve just cleared the long list of codes that were present because I ,ahem, forgot to clear them yesterday doh! I took the car for a spin and the issue is still present but just did another scan and I’m only seeing the P2603 and P0054 (which I suspect is a knock on effect of the first code) so at least it’s narrowed it down to the turbo coolant pump. I’m going to have another look at the connector and check the fuse as the pump was definitely working before it went in the garage so still hoping that it’s a simple fix lol.

[gwest]

The pins on the turbo coolant pump are clearly marked and you can try testing it by applying 12V to the + and ground to the -. That said, if the motor spins I'm not sure if this necessarily exonerates the pump? The ECU grounds the circuit when it activates so if there is any hindrance to earthing at the ECU connector (like dirty oil) then it might be the cause of the pump not working. If this was the case then you might predict that the wires from the turbo pump connect to your middle ECU connector. As well as some wires from devices that might allow capillary action of leaking oil. Like oil pump solenoids, oil pressure sensors, Vanos solenoids, oil level sensors ....

[MarcoDS3]

I’m gonna be giving the ECU connector another good clean today just in case. I haven’t got the right equipment to check the circuit on the pump worse luck so I might have to take a punt on a new pump if I don’t have any luck with the connectors.