Ohms reading = 0 With Igition off and with Ignition on

 

Zero ohms resistance ?
Or infinite resistance ?

 

I dont know probably infinate i tested pin 48 and it measured 524 and keeping the same earth and dial setting ,i moved the positive multimeter probe to pin 1 then got a reading of 1,

I just assumed that was Zero, I thought the 1 was insignificant to mention.

So i take it that my answer should be "infinate"





My teacher told me at school "If you dont pay more attention in class you will end up being a window cleaner"

Guess what I am now a window cleaner.

Thanks for your education

Dave

 

If you touch red to black , that zero resistance . What does the read out say ?

If on the other hand you do not touch red or black to anything at all , that would be infinite resistance .

 

Indycam

Multimeter probes not touching = "1"

probes touching = "000"

for reference

pin 1 to pos lead - earth to neg lead = "1"

same earth to neg and pos to pin 48 = "524"

 

1 = infinite resistance

000 = 0 ohms resistance

"Ohms reading = 0 With Igition off and with Ignition on"
The reading was infinite resistance , not 0 resistance .

 

And infinite resistance is the right thing . If the reading was less than infinite , the wire would be shorting .

 

David,

That was to check for a wiring loom/module short to ground.
Can you check pin 17 ? That is an injector drive . With just ignition on you should have a horizontal line at around +12 volts. When you crank you should see pulses going down to 0 volts.

That would be good to know.

Geoff

 

From way back ,
08-07-2006, 05:57 AM
"Firstly yes i can smell unburnt fuel at the tailpipe,"

 

Dave,

I've been following this thread from the start (I suggested the ECU guy). Some of the comments are just plain unhelpful, I can really sympathise with you! If it's not sorted by next week, I can call you whilst doing the same measurements with a meter and oscilloscope on my 89 C4. If we can go through the diagnostic checks in sequence, we may be able to pin the fault down and get your car going again. I'm away next weekend, but free the following Sunday 4th Feb. I think I'll have to print out the thread to work out what to do first though - could make a good DIY though.

Barry

 

Indycam,
Just wanted to double check that part of the DME was working and that the fuel smell isnt just the injector drivers permanently "on".


Geoff

 

Cool

 

Geoff

Do I test pin 17 with the DME connected or unclipped.

I will have to wait until morning now.

Barry

Thanks for the offer, hopefully it will be ok by then.

It seems strange everything is pointing back to the ECU even though it has been tested.

The six wires which will prevent a spark are all doing there jobs correctly, but no putput from the ECU

Dave

 

"From way back ,
08-07-2006, 05:57 AM
"Firstly yes i can smell unburnt fuel at the tailpipe,""

Indycam is right on, i.e. wasting more time and causing more confusion.
All the diagnostic data is THERE!

 

Dave,
With everything connected .
Does start to look like the pin 1 driver in that DME is toast ! What a PIA.
Looks like you may be making a call to Plymouth or maybe driving up there with a DME under your arm. Dont know if you are a Faulty Towers fan but I was thinking of Basil with the Gnome under his arm !

You must be totally p*ssed by all this.

Geoff