81
T500 9015504 01-2018
TROUBLESHOOTING
i-DRIVE TESTING PROCEDURE
Step
Action
Value(s)
Yes
No
1
Switched (+)*
• Key ON / circuits loaded (preferred)
• All electrical components remain connected
to wire harness
• Use an electrical schematic to identify all
switched (+) power supply wires
• Is there
switched battery voltage
(+) applied
to circuit board?
Applied voltage
must be within
1 volt of actual
battery voltage
Proceed to
STEP 2
Identify voltage
drop location
and repair or
replace neces-
sary compo-
nents
1
2
Unswitched (+)*
• Key ON / circuits loaded (preferred)
• All electrical components remain connected
to wire harness
• Use an electrical schematic to identify all
unswitched (+) power supply wires
• Is there
switched battery voltage
(+) applied
to circuit board?
Applied voltage
must be within
1 volt of actual
battery voltage
Proceed to
STEP 3
Identify voltage
drop location
and repair or
replace neces-
sary compo-
nents
1
3
Negative (-)*
• Key ON / circuits loaded (preferred)
• All electrical components remain connected
to wire harness
• Use an electrical schematic to identify all
negative (-) / ground supply wires
• Is there battery negative (-) applied to circuit
board?
Applied voltage
must be within
1 volt of actual
battery voltage
Proceed to
STEP 4
Identify voltage
drop location
and repair or
replace neces-
sary compo-
nents
1
4
Inputs
• Key ON
• Manually exercise all input devices and use
a multimeter to observe status change
• Use an electrical schematic to identify all
input circuits
• Do all inputs function correctly?
Proceed to
STEP 5
Repair or
replace neces-
sary input
components
1
5
Outputs
• Key ON
• Disconnect battery and circuit board from
wire harness and use a Ohmmeter to test
output circuits for open or shorted circuits
• Use an electrical schematic to identify all
output circuits
• Is there an
open
or
shorted
2 output circuit
causing the trouble symptom?
Repair or re-
place necessary
output compo-
nents
1
Replace circuit
board
1
Wire harnesses are components
2
An open circuit has infi nite resistance “O.L.”. A
shorted circuit has 0 (zero) resistance. Always test
through entire circuit.
* Switched (+) and Unswitched (+) indicate positive
battery voltage applied to circuit board. Negative (-)
indicates battery negative (ground) as part of power
supply to circuit board.
Summary of Contents for t500
Page 5: ...5 T500 9015504 01 2018 CONTENTS ...
Page 55: ...55 T500 9015504 01 2018 TROUBLESHOOTING ...
Page 89: ...89 T500 9015504 01 2018 SERVICE 9 Cycle the key switch to save selections ...
Page 111: ...111 T500 9015504 01 2018 SERVICE ...
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