In this video we diagnose a Peugeot 107 (Toyota Aygo / Citroen c1)
with a b2799 Immo faultcode. (crank no start)
We learn that a continuity test isn’t always the best test…..
For the Topdon tool used in the
video:
https://www.topdon.us/discount/DIAGNOSEDAN10 the price of Phoenix Max will be 10% OFF by clicking the US link
European contact: oscar@topdon.com
Uk :
https://www.diagnosticconnections.co.uk/topdon-trucks-lorry-van-vehicle-diagnostic-tools
For business inquiries ( not for technical questions); Diagnosedan@gmail.com
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The multimeter would have told you that you had a short to ground if you put one lead to chassis ground and the other to the purple wire. Seems like someone was not very careful back probing and created a malfunction.
Thats the way! always the best Dan
Awesome share. Many thanks.
Long talk for nothing.. To check for a short is mandatory in such a case.
Excelent Dan!!! You have something special. I learned a lot of things from yours videos. Thanks a lot!
The first steps to check a signal circuit are to verify no short to ground or power. If that tests passes, the next step is to load test the circuit. Further diagnosis before these tests are complete is a waste of time. The previous shop obviously wasted quite a bit more time than you did. Installing a set of matched parts was totally pointless without fully verifying the integrity of the circuit.
Amazing as always. Thanks Dan
First off, O.L on a multimeter is not "open line". It is called Over Limit. Anyone should have checked the connectors first not continuity tests first. To eager to show off your toy
Good video, thank you. It would be also interesting to see your procedure in fixing the harness up again.
Cool fix mate, but i wonder what the original fault was, the short was obviously created by somebody who was fault finding, and split the crimp open, but surely it wouldnt have been like that from factory, so yes Dan removed the short but what caused them to look in the first place????
I was testing wires for lights like that, and I got continuity from one to all of the wires in the connector, it was because there was always little voltage in each wire. I think disconnecting the battery solved it but im not sure. Multimeter is goving some voltage into the wire and then measuring, maybe it's better to try switching to resistivity measuring
Is there a book written by Dan that goes with these videos?.
Excellent video. What model Topdon scanner and what model scope are you using? Thanks
Dan the Man!!
u r epic bro….u really make stuuf look easy, i enjoy your happiness with this kind of eletrical faults,, please keep up these videos because thanks to you i fixed my a4 with a fuse bad connection
Great video. So comprehensive!
You might not know, but some technical owners may have fitted a secret immobiliser switch to that purple wire to ground it, which can defeat a cleverest of clever thief, I had one such a switch fitted in my car's glove box, by its previous owner, so one day I went out to a hospital, I was given a bundle of papers, which I put in my glove box unknown to me there was a toggle switch which my bundle knocked to immobilised position, luckily for me I was able to start the car by rolling it down a small slope only that this switch did not allow cranking, so i got home, then started to find out why it would not crank, took me a few hours to figure out this hidden switch, I bought this car from a dealer who didn't tell me anything about this hidden switch.
Yes and apart from continuity check on those wires, I would have definitely put my oscilloscope to see any data stream being exchanged or present on those wires, since continuity only tells that the two points are continuously connected, but cannot tell you if data is being transmitted along the wires.
had same issue on Renault Traffic 2. ECU will comm with VDI but would not comm with IC wich contains IMMO. ecu is connected with K line to the obd2 port and CAN line with IC. Even if you have comm with ECU doesn't mean that CAN is ok. No errors in ecu or ic or immo. it was a broken or shorted (can't recollect exactly) to gnd CAN wire. somewhere behind dash. it was pain in the ass to install new wire from interior to the ecu. but it fixed it. from that point i always test wires not only for continuity but for a short to + or – as well.
very good ! you should write a manual 40 years of this an i am still learnin
I had a Citroen BX back in the 1890s. A very underrated car with very little electronics. The alternator charge warning light started coming on. Took alternator to a specialist who said it needed work. Fitted overhauled unit and all seemed well. Then that light came on again. I noticed battery wasn’t going flat as much as you’d expect but whatever. Then I heard a click as the warning light came on. I don’t remember what circuit it was but was able to trace were it went. Lo and behold found a chafed wire over a body seam. That short to earth was tripping a relay which powered the battery side of the charge indicator. So the charge light came on powered by the alternator rather than by the battery which is the more usual direction.
Wire fixed, better protected and problem solved. At least I now had a nice “new” alternator.
Dan what is your opinion of the topdon phoenix max? Is it worth the money and would you recommend it? I’m looking for a scan tool that can do it all. The topdon ticks most of the boxes. Do you agree?
The green wire also was bent out just like the purple wire. Dan is the best! I am an industrial equipment tech, not a car tech, but I’ve been burned by this many times before. Test lights are so much better than DMM’s for this kind of thing.
What an awesome video!
Thank you very much sir.
I have the same problem on a Peugeot 406
What was going on with all the heat shrink connectors above the dash in the part of the loom near the screen on the drivers side? Looks like this poor car would tell a few stories if it could talk.
Excellent presentation of a diagnosis, thank you for your clear explanation!