Testing - Open Circuits, Short to Ground or Positive, etc....

   #1  

DrPeter

Ross-Tech Employee
Joined
Jan 29, 2014
Messages
1,398
Reaction score
2,660
Location
16.4905° S, 151.7375° W
Testing as per fault code description:
by: DrPeter

When you have a fault code, like the ones below, it may be necessary to test the wiring and connections of the circuit before you
condemn a 'good' part and just throw another good part at the vehicle and expect a different result, we all know where that leads us.

The follow steps are intended as a guide to help you properly, quickly and accurately diagnose these types of wiring concerns, you must also
be on the lookout for any obvious connector issues, corrosion, damage, etc...


19559/P3103/012545 - Motor for Intake Manifold Flap (V157): Open or Short to Ground

17506/P1098/004248 - Intake Manifold Tuning Valve Position Sensor (G336): Open or Short to Plus


The first step is to become familiar with how the circuit works, locate a factory wiring diagram and identify the suspect component and see how it is wired.

Note: Ask yourself this, if you do not know how the V157-Motor for intake flap is wired, how can you properly test it, right?
What wire goes where? What wire is the power? Signal return, etc.?







Testing for Short to Ground.

Prerequisites:
- Ignition is turned off
- Disconnect the component(s) connector(s)
- Check wiring diagram and make sure no other components are on the circuit
- Disconnect the controller connector
Testing details:
- Set Digital Volt Ohm Meter (DVOM) to DC Voltage
- One DVOM meter probe to battery positive (+)
- Other probe to wire connection that is being tested (either end)
- Wiggle the harness
- Voltage is less than 0.2-Volts is acceptable
Repair details:
- Search and find the wire short and repair
- Or install an overlay harness




Testing for Short to Positive.

Prerequisites:
- Ignition is off
- Disconnect the component(s) connector(s)
- Check wiring diagram and make sure no other components are on the circuit
- Disconnect the controller connector
Testing details:
- Set Digital Volt Ohm Meter (DVOM) to DC Voltage
- One DVOM meter probe to battery negative (-)
- Other probe to wire connection that is being tested (either end)
- Wiggle the harness
- Voltage is less than 0.2-Volts is acceptable
Repair details:
- Search and find the wire short and repair
- Or install an overlay harness



Testing for Open Circuits.

Prerequisites:

- Ignition is off
- Disconnect the component(s) connector(s)
- Check wiring diagram and make sure no other components are on the circuit
- Disconnect the controller connector
Testing details:
- Set Digital Volt Ohm Meter (DVOM) to Ohm setting
- DVOM meter probes each end of the wire to be tested
- Wiggle the harness
- Resistance of 3-Ohms or less is acceptable
Repair details:
- Search and find the open/damaged wire and repair
- Or install an overlay harness




Testing for Wire Shorted to Other Wires.

Prerequisites:
- Ignition is off
- Disconnect the component(s) connector(s)
- Check wiring diagram and make sure no other components are on the circuit
- Disconnect the controller connector
Testing details:
- Set Digital Volt Ohm Meter (DVOM) to Ohm setting
- DVOM meter probe to first wire to be tested (either end)
- DVOM meter probe to other wire to be tested (either end)
- Wiggle the harness
- Resistance of 9-MOhm or more is acceptable
Repair details:
- Search and find the wire short and repair
- Or install an overlay harness



For more information about the use of a DVOM please see the following links:

http://assets.fluke.com/appnotes/automotive/beatbook.pdf

http://www.electronics-lab.com/articles/multimeter_tutorial/

http://support.fluke.com/find-sales/Download/Asset/1260898_6116_ENG_M_W.PDF
 
   #3  

WuMutien

Verified VCDS User
Verified
Joined
Apr 27, 2015
Messages
40
Reaction score
21
Location
Atlanta, GA USA
VCDS Serial number
C?ID=245683
Might this thread be a sticky?
 
  • Like
Reactions: Uwe
   #4  

Chericon

Verified VCDS User
Verified
Joined
Jan 31, 2017
Messages
4
Reaction score
0
Location
USA
VCDS Serial number
C?ID=75121
Whats the controller connector? I take it the component connector would be the connection to the component in question. In my case its the evap purge calve
 
   #5  

Chericon

Verified VCDS User
Verified
Joined
Jan 31, 2017
Messages
4
Reaction score
0
Location
USA
VCDS Serial number
C?ID=75121
What is the controller connector?
 
   #6  

Uwe

Benevolent Dictator
Staff member
Joined
Jan 29, 2014
Messages
29,964
Reaction score
21,398
Location
USA
VCDS Serial number
HC100001
Component Connector is the connector "plug" where the component (switch, sensor, actuator) plugs into the car's wiring harness.

Controller Connector is is the connector "plug" where the control module in question plugs into the car's wiring harness.

In some cases, control modules (and less commonly, components) may have more than one connector.

-Uwe-
 
   #7  

TdiBlacky

Verified VCDS User
Verified
Joined
Nov 30, 2016
Messages
5
Reaction score
1
Location
Ireland
VCDS Serial number
C?ID=277924
Testing for Short to Positive.

Prerequisites:
- Ignition is off
- Disconnect the component(s) connector(s)
- Check wiring diagram and make sure no other components are on the circuit
- Disconnect the controller connector
Testing details:
- Set Digital Volt Ohm Meter (DVOM) to DC Voltage
- One DVOM meter probe to battery negative (-)
- Other probe to wire connection that is being tested (either end)
- Wiggle the harness
- Voltage is less than 0.2-Volts is acceptable
Repair details:
- Search and find the wire short and repair
- Or install an overlay harness

I'm trouble shooting the following fault:

00562 - Sensor for oil level / Temperature (G266) 010 - Open or Short to Plus

I'm trying to apply the above instructions but I don't understand how there can be any volts, even 0.2 volts if you disconnect the component connector plug and the module connector plug and also the ignition is off. Surely there should be no volts in this scenario?
 
   #8  

Uwe

Benevolent Dictator
Staff member
Joined
Jan 29, 2014
Messages
29,964
Reaction score
21,398
Location
USA
VCDS Serial number
HC100001
I'm trouble shooting the following fault:

00562 - Sensor for oil level / Temperature (G266) 010 - Open or Short to Plus

I'm trying to apply the above instructions but I don't understand how there can be any volts, even 0.2 volts if you disconnect the component connector plug and the module connector plug and also the ignition is off. Surely there should be no volts in this scenario?
Post a snippet of the wiring diagram for this sensor please.

-Uwe-
 
   #10  

Uwe

Benevolent Dictator
Staff member
Joined
Jan 29, 2014
Messages
29,964
Reaction score
21,398
Location
USA
VCDS Serial number
HC100001
If you don't have a wiring diagram or know where the sensor is, it's really pretty difficult to help you trouble-shoot it.

May I suggest that you register for and then pay for the minimum-length eRWin subscription and grab all the stuff specific to your car?

-Uwe-
 
   #11  

Jack@European_Parts

NostraJackAss
Joined
Jan 29, 2014
Messages
20,382
Reaction score
8,728
Location
Montgomery, NY, USA
VCDS Serial number
C?ID=57337
When in an area of the unknown, try to get RTFB as aforementioned, always check all fuses & one at a time; consider the use of a tone generator to trace.



Then load or light a track, verifying the track can carry current.........
 
Top