P0489 – EGR control circuit low HELP ME PLEASE

[illscrapit]

Hi all,

I’m looking for some help diagnosing an EGR fault on a Citroen 1.6 HDi (DV6 engine).

Originally, the car had a stuck EGR valve fault, so I replaced the EGR valve with a new Pierburg unit and cleaned the throttle body / air doser at the same time.
After doing that, the original EGR stuck fault went away, but I now have a new fault code: P0489 – EGR control circuit low, and the engine management light remains on.

Here’s what I’ve done so far:

Replaced the EGR valve with a new Pierburg unit
Cleaned the throttle body / air doser
Checked the wiring plug at the EGR
Checked voltages at the EGR connector:

Pin 1 = 0V
Pin 2 = ~12V
Pin 3 = 0V
Pin 4 = ~12V
Pin 5 = 5V reference

------------------------
checked continuity;
Pin 1 = open circuit
Pin 2 = open circuit
Pin 3 = 0.04-0.08
Pin 4 = open circuit

Pin 5 = open circuit
So I appear to have power, ground, and 5V reference present
Fault P0489 still remains and engine light stays on

My questions;

Which pin is the ECU control wire on the 5-pin EGR connector for the 1.6 HDi?
Has anyone had a broken wire in the EGR loom causing P0489?
Are there any common fuse or relay issues that can cause P0489 on this engine?

Any help from someone familiar with the PSA 1.6 HDi would be massively appreciated, as I feel like I’m close to the problem but want to confirm before I start cutting into the loom.

Thanks in advance.

[mickthemaverick]

When you say open circuit on those pins, open circuit between the pin and where?

[illscrapit]

testing from the pins to the negative battery terminal.

[mickthemaverick]

What is the voltage reading across the battery terminals with the ignition off, and with the Engine running, and when cranking?

[illscrapit]

ignition off: 12.25V
engine on: 14.60V
crank: drops to 10.60V from 12.25V then climes up to 14.60V

[mickthemaverick]

Ok then your battery is knackered. Should have a minimum of 12.7 when ignition off and stay above 12.3 when cranking. Charging sounds ok but the ECU is detecting low volts at the beginning and throwing the code. First thing is to give the battery an overnight charge, refit and carry out the BSI reset procedure in the link I'll edit in in a bit. Then try the tests again. If the cranking still goes low then time for a new battery.

BSI RESET:

viewtopic.php?p=601679#p601679

[illscrapit]

I removed the battery and charged it overnight, then tested voltages:

Ignition off: 12.48V
Engine running: 14.60V
During cranking: drops to about 11V

So I think the battery may be on its way out and I will be replacing it.

I also found a snapped earth strap from the gearbox to under the battery tray, which I have now replaced.

With the EGR unplugged, I can run the engine and clear the codes and the P0489 code disappears, but I then get P0405 – EGR Sensor A Circuit Low (which I believe is normal because it’s unplugged).

However, as soon as I plug the EGR back in, the P0489 fault comes back immediately.

I also tested the EGR supply voltage to battery negative and it drops to about 7V while cranking.

While I’m waiting to replace the battery, are there any other tests I should be doing?

[mickthemaverick]

I would wait till you have replaced the battery now. Don't forget to do the BSI reset when you fit the new battery.

[illscrapit]

Roger that, ill be back with an update soon.

[RichardW]

Looks to me like the new EGR valve is either duff or the wrong one with an incorrect pin out. If you plug the original valve back in what happens? What year is the car / which version of the engine?

[illscrapit]

Good evening,

Here are the car’s details:
REG: EY64 OBK
Model: C4 Grand e-HDi Airdream Exclusive Plus ETG6
VIN: VF7**************[VIN obfuscated, can be read by forum staff]
Engine: DV6C (9HC)

I originally replaced the EGR valve with a cheap aftermarket one from eBay (£50). This got rid of the P0409 (valve detected jammed closed) fault, but then I got a P0489 fault code after fitting it.

I then purchased the original Pierburg EGR valve (£256). I have checked it and all the part numbers match the original unit that came off the car. and am still getting the same P0489 code

[RichardW]

Might be some useful info in here: https://www.peugeotforums.com/threads/p ... nt.366924/ that turned out to be some issue with vac hoses - are there vac hoses to the EGR valve?

[illscrapit]

Good evening all,

I’ve fitted a new Bosch battery and carried out a BSI reset. I have now plugged everything back in and I am getting 12 fault codes, which are as follows:

No. Code Description
1 P1694 Fault on starter motor control line
2 P2291 Injection rail pressure rise too slow on starting
3 P1162 EGR valve jammed open during ECU sleep phase
4 P12B3 EGR valve position incorrect (too open)
5 P0489 EGR control circuit / position incorrect
6 P0113 Intake air temperature sensor circuit fault
7 P0102 Mass air flow sensor signal too low
8 P0405 EGR position sensor circuit low / open circuit
9 P2144 EGR control electrical fault
10 P0409 EGR position sensor fault
11 U1318 CAN communication fault with BSI

i am unable to remove any of them with the scanner.