Fault code 03 is the ECU fooked?

[supadik]

Hi guys.

I have an M plate Chimaera 400 HC which may have a dead ECU Here's what happened. The car had been stood for a while so the battery had gone flat. I went through the usual faff of removing the passenger-side kick panel so I could slide the battery box out to charge the battery. Once the battery was charge I started the car and surprise surprise it had a misfire. I spent the afternoon tracking down the cause which turned out to be a dodgy spark plug on No.2 cylinder. With the plug swapped it was running fine so I switch off and pushed the battery box back into place, slid the ECU back in place between the battery box and the side of the foot well and stuffed the wiring back as neatly as possible (not very) and replaced the kick plate. I then sodded off back indoors to scoff my tea. A few day later I decided to take the car for a run, switched on the ignition and noticed the fuel pump wasn't buzzing. I checked the fault code reader which was showing code 03 - corrupt data. I disconnected the battery for hmmm 30 seconds and got code 02 as I expected. I turned off the ignition to clear the 02 code but when I turned the ignition back on code 03 returned. So my question is is the ECU fooked or am I missing something? The harness is secure on the ECU and the relays are all in place is there anything else that could cause the 03 code such as a blown fuse or something?

It's probably unrelated but when I was last using the car regularly the speedo's mileage counter (digital) had reset itself to zero and did so every time I turned the ignition off followed a few weeks later by the speedo crapping out all together leaving me having to guess my speed, it's prob not relevant to the ECU issue but thought I'd best mention it just in case.

I await you wise and insightful answers

[blitzracing]

Try reseating the internal eprom in its socket. The Error code is not very specific as to where the checksum (data error) is occurring.

[supadik]

You mean open the ECU and make sure the Eprom is sat in it's socket properly? (hands already shaking lol)

[blitzracing]

Yes its not scary, just remove the torx screws from around the ECU case and carefully split it. The PCB is loose inside once you have split it, so keep the PCB on one half of the ECU with the components facing upwards. The Eprom a large brown chip is in a socket, normally with a bit of black tape and a label with the spec like "3.9 cat". Just get a small screwdriver under the chip in lift it 1 or 2 mm at both ends and then push it back down. Thats all that's needed. If that does not work you can try another chip ( I have a few if you want to try), or another ECU should be less than £100 from a Range Rover breaker, but you will need to swap the chip across. Avoid early (Pre 1993 ECU's) they wont be compatible. Dont pay "TVR" prices. I payed around £35-50 for the last few I bought.

[supadik]

Thanks for the above advice. I had a heavy night at the pub last night so I'll get a few cups of tea down me before I start fiddling with the ECU as my hands are a bit shakey at the moment

[supadik]

Ok I've lifted and reseated the Eprom and also checked the fuses and relays but I still get fault code 03 and no power to the fuel pump. luckily the crappy minature toy town I live in happens to have a landrover breakers that has broken lots of rangies and discos so I should be able to pick up an ECU quite cheap. Are there any numbers/codes that need to match my ECU or will any 14CUX ECU made after 92 accept my Eprom? This may be a stupid question but if the ECUs are all sat on a shelf how do I tell it's manufacture date?

[Bodmin]

The ECU TVR use is Land Rover AMR2175 although as Blitz has advised other Land Rover part number models will also fit although their wiring connector position may be in an alternative position i.e. on the side.

The earlier ECUs also had a soldered in Eprom chip as opposed to the later socket type Eprom fitting which you need. There is a date code on the ECU identification sticker i.e. 2196 is week 21 of 1996.

Bodders

[supadik]

Thanks for that, I'll make sure I get the right one. Anybody have a rough idea what I should be paying?

[supadik]

Well my local range rover breakers don't have one So any suggestions who/where to try would be helpful. Just to double check, am I right in thinking that I would ideally want a post 1993 ARM2175 but if pushed any post 1993 to about 1996 14cux will do???

[blitzracing]

yes, check out Ebay as with most things. There is one on there at the moment marked 1992 / 3 but I cant say if the chip is soldered in or not. The pluggable units have a big plastic cover over the whole fuel chip and socket, that are like this when the cover is removed. If there is no cover the chip can be seen to be soldered in.

[supadik]

cheers for that Blitz, there's a couple on fleebay at the moment so I'll grab one and open it up when it arrives to see if the chip is swapable. if it is I thought I'd connect the new ecu with it's original chip first and make sure all is well and then swap the chip for the one in my original ecu. I thought it would be better to do it that way as I don't know if it's my ecu or the chip that's failed.

[supadik]

Well now, I got a new (to me) ECU off fleebay for £20 I fitted the new ECU but the problem remained...so even though I had checked the main power and fuel relays (I was V hung over at the time) I removed the fuel relay, bridged the connector with a paper clip and the fuel pump started running, so I cranked the car and it fired straight up.

So I've bought a new relay (£13 from Pages) and everything is fine. I left the original ECU in place so I'll keep the new one as a spare.

I'm not sure what the moral of this story is, maybe something to do with diagnosing electrical faults whilst hungover (all though I'm against anything that discourages drinking) or start with the cheapest option 1st.

Anyway thanks to everybody who offered advice, especially Blitz, I just hope the sunny weathers comes back for one more weekend before the snow gets here lol.

[blitzracing]

Its possible that if the ECU did not get the full 12 volts it could throw up a false code...

[supadik]

Well just to update this very very old thread (it may help others) I have had the Chim parked up unused for well over a year. Last week I decided I'd make sure it still ran before I respray it. I'd charged the battery up about a month earlier and left it in the back garden...well actually I left it on the kitchen counter next to the bread bin, my wife moved it to the garden!!!! Once fitted to the car it was clearly nearly dead again so I hooked up my jump starter and cranked it over. She turned over ok but didn't fire up. I checked the ecu codes and had 02 followed by 03 again so it does seem that below a certain voltage the ecu will throw up the 03 fault code as Blitz suggested.

I'll charge the battery up over the weekend and try firing the car up and report back here.