running too rich.
#21
03-30-2012, 05:44 PM
#23
03-30-2012, 08:51 PM
Just in case we are at cross purposes, according to my diagram the pins on the ECU North American emissions spec ECU and the wires to them have different colours than UK spec. The pins numbers read RHS to LHS (opposite direction to a book) and numbers start at the bottom row RHS. My diagram says for North Amercian spec:
Pin 5 feeds 5v to the CTS wire colour code UC (do not know what that codes is, sorry).
Pin 7 is the return from the TPS wiper and is colour code YB wire. This carries the variable voltage from the TPS to the ECU.
Pin 19 (top row first pin on RHS) is the other, non-wiper, wire from the TPS and is also colour code YB that also is joined to the return from CTS. So both these YB wires from the TPS and CTS go to the same pin. BUT the colour code on the wires to pin 7 (TPS wiper voltage signal indicating throttle position) and pin 19 is the same, even though they seem to have separate functions. So knowing which YB wire you are testing is important, as they must carry different voltages.
Pin 20 is 5v feed to the TPS and the air temp sensor (code YK).
Pin 21 is the return from the Air temp sensor (colour RU, but I do not know what that colour code is either).
So these five pins between them cover all the inputs and outputs from the ATS, CTS and TPS.
Greg
Pin 5 feeds 5v to the CTS wire colour code UC (do not know what that codes is, sorry).
Pin 7 is the return from the TPS wiper and is colour code YB wire. This carries the variable voltage from the TPS to the ECU.
Pin 19 (top row first pin on RHS) is the other, non-wiper, wire from the TPS and is also colour code YB that also is joined to the return from CTS. So both these YB wires from the TPS and CTS go to the same pin. BUT the colour code on the wires to pin 7 (TPS wiper voltage signal indicating throttle position) and pin 19 is the same, even though they seem to have separate functions. So knowing which YB wire you are testing is important, as they must carry different voltages.
Pin 20 is 5v feed to the TPS and the air temp sensor (code YK).
Pin 21 is the return from the Air temp sensor (colour RU, but I do not know what that colour code is either).
So these five pins between them cover all the inputs and outputs from the ATS, CTS and TPS.
Greg
so according to this diagram i should in theory be able to splice pin 5 to both the CTS and TPS and effectively achieve my 5v output. thanks for this post.
#24
03-31-2012, 01:42 AM
Veteran Member
Greg
#25
03-31-2012, 03:48 AM
Veteran Member
M can you remove the connector from the ECU and remove the connectors from the CTS ATS and TPS then measure each wire to ground, (bearing in mind that the problem or short might be intermittent).
What you are looking for is NO continuity. I suspect you have a wire shorted to ground. I have been fixing electronics for 30 years and I think you have a loom issue. Once the loom is ruled out then start looking for other issues, first rule in fault finding is start at one end and rule out the easiest parts first, DO NOT move on until you are 100% certain.
Wire colour codes
The first code is the major colour and the second is the trace.
B = black
N = Brown
R = Red
O = Orange
G = Green
U = Blue
P = Purple
LG = Light Green
S = Grey
W= White
Not sure what C is
What you are looking for is NO continuity. I suspect you have a wire shorted to ground. I have been fixing electronics for 30 years and I think you have a loom issue. Once the loom is ruled out then start looking for other issues, first rule in fault finding is start at one end and rule out the easiest parts first, DO NOT move on until you are 100% certain.
Wire colour codes
The first code is the major colour and the second is the trace.
B = black
N = Brown
R = Red
O = Orange
G = Green
U = Blue
P = Purple
LG = Light Green
S = Grey
W= White
Not sure what C is
#27
03-31-2012, 06:45 AM
Veteran Member
Because if the insulation is broken and exposing the wire to ground your voltage can be going to ground and never making it to the end. Electricity always takes the path of least resistance. You will still have continuity (ohms) with a short.
Think of it this way, if you make a Y with your wires, and put your ohm meter on 2 leads and ground the third, you will still have continuity.
Think of it this way, if you make a Y with your wires, and put your ohm meter on 2 leads and ground the third, you will still have continuity.
#28
03-31-2012, 07:59 AM
Have you tried putting your old TPS back in yet?
Jumping blu/or to get 5v to the TPS is not a permanent fix and it also doesn't get you anywhere in your faultfinding. All you do is risk burning up another ECU. Rebuild the harness to the TPS / CTS / IAS - it will take you fiften minues, you can then tell all of us that we're wrong and we can start looking elsewhere. Even if it's not the problem, it probably needs to be done anyway.
D
Jumping blu/or to get 5v to the TPS is not a permanent fix and it also doesn't get you anywhere in your faultfinding. All you do is risk burning up another ECU. Rebuild the harness to the TPS / CTS / IAS - it will take you fiften minues, you can then tell all of us that we're wrong and we can start looking elsewhere. Even if it's not the problem, it probably needs to be done anyway.
D
#29
03-31-2012, 04:14 PM
Because if the insulation is broken and exposing the wire to ground your voltage can be going to ground and never making it to the end. Electricity always takes the path of least resistance. You will still have continuity (ohms) with a short.
Think of it this way, if you make a Y with your wires, and put your ohm meter on 2 leads and ground the third, you will still have continuity.
Think of it this way, if you make a Y with your wires, and put your ohm meter on 2 leads and ground the third, you will still have continuity.
Have you tried putting your old TPS back in yet?
#31
03-31-2012, 04:30 PM
Veteran Member
Everybody here has said rebuild your harness first. I think you need to take this advice and before you start replacing this and rebuild that DO THE HARNESS. You are not going to fix this by jumping all over the place.
Once the harness is rebuilt and confirmed as good, then if you still have a problem move onto the next item in the chain. If you do it this way you stand a chance of actually fixing the problem.
Once the harness is rebuilt and confirmed as good, then if you still have a problem move onto the next item in the chain. If you do it this way you stand a chance of actually fixing the problem.
#32
03-31-2012, 04:42 PM
well i found out why Jag didnt run the TPS and CTS with the same 5v output.... because you only get 3v to each sensor if you splice the 5v supply from the CTS.
that being said, the only reason why pin 7 could possibly not put out 5v is if its got no input voltage from the harness. i just wish i knew where to start. my schematic is too vague. anyone have a schematic of the ECU circuitry itself? apart from the harness wiring?
that being said, the only reason why pin 7 could possibly not put out 5v is if its got no input voltage from the harness. i just wish i knew where to start. my schematic is too vague. anyone have a schematic of the ECU circuitry itself? apart from the harness wiring?
#33
03-31-2012, 04:51 PM
Veteran Member
Forget what is happening in ECU you DO NOT KNOW where the problem is yet. The only way is a process of elimination and the harness is the easiest to fix and the MOST likely to be your problem.
#34
03-31-2012, 04:55 PM
#35
03-31-2012, 05:09 PM
Veteran Member
I have been fixing electronics for 32 years so I know what I am talking about, and the way you are going about this there is little to no chance that you will fix it.
#37
03-31-2012, 06:04 PM
Please stop everything you are doing and listn to what everyone is telling you.
STOP jumping everything all over the place. This is how you fry ECUs.
BEFORE YOU DO ANYTHING ELSE REBUILD YOUR HARNESS.
Everything you are seeing is indicative of crispy shorted wiring under the hood. Stop what you are doing and rebuild he harness. It wll take you two hours.
Then, if the problem still exists, you have now eliminated the MOST COMMON sourcefor behavior like this.
Stop jumping things all over. You are not getting anywhere by doing this.
STOP jumping everything all over the place. This is how you fry ECUs.
BEFORE YOU DO ANYTHING ELSE REBUILD YOUR HARNESS.
Everything you are seeing is indicative of crispy shorted wiring under the hood. Stop what you are doing and rebuild he harness. It wll take you two hours.
Then, if the problem still exists, you have now eliminated the MOST COMMON sourcefor behavior like this.
Stop jumping things all over. You are not getting anywhere by doing this.
#38
03-31-2012, 06:28 PM
Veteran Member
Did you cut the wires at the ECU or did you just splice into the wire that is there?
If you spliced into the wire and left it connected to the ECU then if that wire has a short that short is still in the circuit.
What I would do and in this order is:
Check the earthing - measure resistance of ECU case to ground, then measure engine to ground, ground will be chassis. Both should be less than 1ohm. If this is good
Then remove the connector prior to the engine bay - this is located behind the front wheel, you will need to remove the inner section just behind the wheel and you will see a large rectangular connector (there is one on each side of the car, I would think it would be one on the Left) just trace the TPS wires back to the plug.
Once this plug is disconnected ALL of the engine bay wiring is isolated then measure voltages from these pins. This is direct from the ECU. If voltages are correct here then you have an engine bay wiring issue.
If you have incorrect voltages here then we will look further but do this first and report back.
#39
03-31-2012, 06:40 PM
How did you do that?
Did you cut the wires at the ECU or did you just splice into the wire that is there?
If you spliced into the wire and left it connected to the ECU then if that wire has a short that short is still in the circuit.
What I would do and in this order is:
Check the earthing - measure resistance of ECU case to ground, then measure engine to ground, ground will be chassis. Both should be less than 1ohm. If this is good
Then remove the connector prior to the engine bay - this is located behind the front wheel, you will need to remove the inner section just behind the wheel and you will see a large rectangular connector (there is one on each side of the car, I would think it would be one on the Left) just trace the TPS wires back to the plug.
Once this plug is disconnected ALL of the engine bay wiring is isolated then measure voltages from these pins. This is direct from the ECU. If voltages are correct here then you have an engine bay wiring issue.
If you have incorrect voltages here then we will look further but do this first and report back.
Did you cut the wires at the ECU or did you just splice into the wire that is there?
If you spliced into the wire and left it connected to the ECU then if that wire has a short that short is still in the circuit.
What I would do and in this order is:
Check the earthing - measure resistance of ECU case to ground, then measure engine to ground, ground will be chassis. Both should be less than 1ohm. If this is good
Then remove the connector prior to the engine bay - this is located behind the front wheel, you will need to remove the inner section just behind the wheel and you will see a large rectangular connector (there is one on each side of the car, I would think it would be one on the Left) just trace the TPS wires back to the plug.
Once this plug is disconnected ALL of the engine bay wiring is isolated then measure voltages from these pins. This is direct from the ECU. If voltages are correct here then you have an engine bay wiring issue.
If you have incorrect voltages here then we will look further but do this first and report back.
#40
03-31-2012, 06:59 PM
Veteran Member
My circuit diagram has no pinouts on the ECU I'll have to do some research
GO and measure the resistance to ground as I said in my last post