Cleaned my MAF now Check Engine Light on and no power

Post by **Welly** » Mon Sep 11, 2006 8:51 am

Don't know if it's a coincidence or not but I cleaned the little metal sensor strips in the air flow meter and to begin with it was good.

I was even going to post up here how it seemed to make the car a bit better on the throttle!

This morning though the Check Engine Light came on with a loss of power

The two things may not be connected, but any advice please ?

turbolag · Post by **turbolag** » Mon Sep 11, 2006 9:44 am

Check the connector to the MAF is pushed fully home.

Post by **Welly** » Mon Sep 11, 2006 9:56 am

But I never unplugged it

I used Petrol

on a cotton bud to clean up and was very very carefull.

Blue406 · Post by **Blue406** » Mon Sep 11, 2006 3:57 pm

Check engine + loss of power. Seems to me the ECU has kicked into failsafe mode? The question is, why?

Post by **Welly** » Wed Sep 13, 2006 2:23 pm

The results are in:

The following fault codes have been found on my ECU:

P1404 - ECU fault / Glow Plug Control Module/Relay
P1403 - Engine Coolant Heater (radiator fan !) Wiring fault/Fan Relay/ECU fault
P1408 - Engine Coolant Heater (rad fan) Control - Wiring/ECU fault/Battery
P0221 - Throttle Potentiometer (this could be an old code because this was changed last may at a Peugeot Dealer (famous for forgetting to reset the codes)

So anyway, with my complete lack of equipment and knowledge for the testing of relays and fault finding, the car is going to my Independant Garage friend next week.

I actually think (putting 2 and 2 together) that the classic 'Fan Relay' problem has occured as per Foggy's post the other day. It's a bit strange how it brought on the ECU light though although if the relay sends the wrong Voltage to the ECU it will Bring the Check Light on so maybe I was unlucky here? eventually i suppose I would have got the Coolant Temperature Too High warning.

Does anyone else think the Fan Relay(s) could give rise to a Check Engine Light Fault? If the ECU gets a dodgy voltage back to it then it sees it as an incorrect value and brings on the Check Light (apparently).

chili · Post by **chili** » Wed Sep 13, 2006 4:17 pm

how are you able to read the codes so easily ? do you have a code reader of your own.

Post by **Welly** » Wed Sep 13, 2006 4:51 pm

chili wrote:how are you able to read the codes so easily ? do you have a code reader of your own.

It is my Independant Garage with an extremely expensive Diagnostic Machine

Foghorn Leghorn · Post by **Foghorn Leghorn** » Wed Sep 13, 2006 8:20 pm

This is the kind of problem I dread, and is the problem with modern cars. They rely on so many different ECUs to control anything and when something does go wrong (like a relay for example) its like looking for a needle in a haystack, bad news for us tight wads *cough* I mean home mechanics

Did your Indy garage reset the fault codes for you? Which ones came back?

The two coolant ones could be for the same fault, when my resistor failed I only got a STOP light flash, centre console message and a beep, I didn't get the MIL light coming on. I'd whip your grill off and have a good poke around the two resistors, fan assembly itself, wiring loom and the relays, beg borrow or steal yourself a DVM from someone (you can also pick up a reasonable digital one for <£10 ).

Hopefully the fact that you cleaned the MAF the day before is just a coincidence, I would have thought if it was damaged you'd have got fault lights up straight away.

As for the last one I'd have a good fiddle around with the connections to your glowplugs, check the fuse etc

Fog

trem1 · Post by **trem1** » Wed Sep 13, 2006 8:21 pm

brain not working well at the mo but wtf is a maf

Foghorn Leghorn · Post by **Foghorn Leghorn** » Wed Sep 13, 2006 8:33 pm

I think it stands for Mass Air Flow, its a mesh thingy that sits in the air intake just after the air filter and monitors the air flow. It sends the info back to the ECU so it can adjust the air fuel mixture to keep the ratio correct.

Fog

Post by **Welly** » Thu Sep 14, 2006 8:47 am

The Codes would not reset as the faults are still 'live'.

We will have to start with the fan relays, power down the ECU, then go for a drive, check codes, etc etc, we can even do a driving/live ECU code read and feed it back to the Diagnostic machine to determine what caused the fault whilst you were driving and what other systems were operating at the time (for elimination).

When the Codes first came up they were only 'General Headings' there were 4 but were called:

Pre heater control circuit
Re heater control circuit
Throttle sensor 2 circuit
Alarm/immobiliser security failure........WTF?

Then you have to dig deeper into the 'P' references to see in more detail to narrow it down.

It will be a bit of a ball ache but at least we can start with the favourites, then do another test, then move onto the next etc until the ECU is clear.

Foggy, do you know how much the fan relays cost?

Foghorn Leghorn · Post by **Foghorn Leghorn** » Thu Sep 14, 2006 7:43 pm

Welton wrote:Foggy, do you know how much the fan relays cost?

Relays are quite cheap typically around £5, depends on Peugeots mark up though, shouldnt be too much more.

Fog

Foghorn Leghorn · Post by **Foghorn Leghorn** » Thu Sep 14, 2006 8:00 pm

Welton

Have a good look at the connectors just in front and under the air filter/battery, they are prone to water ingress and corrosion, and at a guess would be close to your MAF

. Hopefully you may have just disturbed them, pull them apart and give them a good clean out and check the earth connections for corrosion (Vaseline comes in very handy here).

Fog

Post by **Welly** » Thu Sep 21, 2006 6:00 pm

I wrote:
P1404 - ECU fault / Glow Plug Control Module/Relay
P1403 - Engine Coolant Heater (radiator fan !) Wiring fault/Fan Relay/ECU fault
P1408 - Engine Coolant Heater (rad fan) Control - Wiring/ECU fault/Battery
P0221 - Throttle Potentiometer (this could be an old code because this was changed last may at a Peugeot Dealer (famous for forgetting to reset the codes)

Well, after all that the problem appears to be the Radiator cooling fan itself!

It is drawing 48 Amps because it is worn and it is making the 40 amp fuse serving it run hot, this in turn has affected the voltages back to the ECU. A new 40 amp fuse has cured it for now as it is handling the current better than the old fuse, the fan relays have been tested over 30 times and have come back with no faults on a testing do-dad.

The 40 amp fuse also has something to do with the glow plugs circuit, hence the fault codes.

My mechanic commented that the pug ECU is not very good at explaining what's wrong with it, it's a bit thick, I mean who would think that a worn out fan motor would give you all these codes?

The ECU is reset now and no faults found (with new fuse in place).

BUT, I need a new fan.....Where shall I get one from (I want a brand new one, no messing around with old parts).

Puggy dealer said £129.00 inc VAT.

Is it easy to fit yourself??

jameslxdt · Post by **jameslxdt** » Thu Sep 21, 2006 6:58 pm

do you have single or twin cooling fans?