Toyota 7BPUE15 Service Manual page 62

Toyota Orderpicker Model 7BPUE 15 Service Manual
DO NOT continue until this condition is
corrected. Your meter may be damaged if
you proceed before correcting this
condition.
N : Depending on the nature of the problem,
O TE
it may also be necessary to measure for
shorts to frame, B+ (truck) or B- (truck)
a t specific circuits associated with the
problem.
a. To identify the cause of the short to
frame, disconnect circuit components
until the low resistance condition
disappears. Do not reconnect
components one a t a time, but leave
them disconnected until the low
resistance reading disappears. Prevent
disconnected terminals or connectors
from touching the truck frame or other
conductive surfaces.
b. The most likely areas to check are:
Motors
Heat sinks
Power cables
Power circuit components
Control circuit components
c. Repair or replace the component
causing the low resistance condition,
Then repeat Step
d. Reconnect all other components
previously disconnected, one a t a time,
measuring resistance between steps. If a
reading is less than 1000 ohms when
reconnecting a component, that
component or its wiring is defective;
repair or replace a s appropriate.
e. When, after all components are
reconnected, you get readings greater
than 1000 ohms, continue with the next
step.
5. Reconnect the battery connector to the
truck and turn the key switch ON. If the
battery was previously removed, ensure
the battery case does not touch the truck
frame.
Use a volt/ohm/ammeter on the current
6.
function meter to measure leakage current
to the truck frame from B+, B-, and all
00700-CL222-05, 1 5 March 2005
4.
Section 5. Troubleshooting
fuses and motor terminals. Begin
measuring a t the highest ampere scale
and work toward the lowest. If the current
is less than 0.001 ampere (1 mA), go to
step If the current is more than 0.001
7.
ampere (1 mA), continue with the step
below.
a. To identify the cause of the short to
frame, disconnect circuit components
until the leakage current reads less than
0.001
A
components one a t a time, but leave
them disconnected until the leakage
current reads less than 0.001 ampere
(1 mA). Prevent disconnected terminals
or connectors from touching the truck
frame or other conductive surfaces.
b. The most likely areas to check are:
Motors
Heat sinks
Power cables
Power circuit components
Control circuit components
c. Repair or replace the component(s)
causing the leakage current.
Repeat step 6.
d. Reconnect all other components
previously disconnected, measuring
current between steps. If a reading is
more than 0.001 A (1 mA) when
reconnecting a component, that
component or its wiring is defective.
Repair or replace a s appropriate.
7. When, after all components are
reconnected, you get a reading less than
0.001 ampere (1 mA) there is no short to
frame condition with the truck or the
battery. If you previously removed the
battery from the truck, re-install the
battery.
Shorts to Frame Test