INTERMITTENT AND POOR CONNECTIONS
Most intermittent electr ical problems are ca used
by faulty elect rical connections or wiring. It is also
possible for a st icking com pon ent or rela y to cau se a
pr oblem. Before condem ning a component or wirin g
assembly, check the following items.
• Con nector s a re fully seated
• Spread ter min als, or terminal push out
• Terminals in th e wiring a ssem bly a re fully
seated into the connector /component a nd locked int o
position
• Dirt or corrosion on the termina ls. Any amou nt
of corrosion or dir t could cau se an inter mittent prob-
lem
• Da maged conn ector/com ponent casing exposing
the item t o dirt or moistur e
• Wire insu lation t hat has rubbed through ca using
a sh ort to groun d
• Some or all of th e wir ing stra nds br oken in side
of the insu lation
• Wirin g broken in side of the in sulation
TROUBLESHOOTING WIRING PROBLEMS
When trou bleshoot ing wirin g pr oblems ther e ar e
six steps which ca n a id in the procedure. The steps
are listed a nd expla ined below. Always check for non-
factory item s added to the vehicle before doing any
diagnosis. If the veh icle is equipped wit h th ese items,
disconnect th em to verify these a dd-on items a re not
the ca use of t he problem.
(1) Verify the problem.
(2) Verify an y related sym pt oms. Do this by per-
forming oper ational checks on component s t hat are
in the sa me circuit. Refer to th e wir ing diagrams.
(3) Analyze the symptom s. Use th e wiring dia-
gra ms t o determ ine wh at the cir cuit is doing, wh ere
the pr oblem most likely is occu rring and where the
diagnosis will continue.
(4) Isolate the pr oblem area.
(5) Repair t he problem ar ea.
(6) Verify the proper oper ation. For this st ep,
check for proper operat ion of all item s on t he
repaired circuit. Refer to the wir ing diagrams.
STAN DARD PROCEDU RE
ELECTROSTATIC DISCHARGE (ESD) SENSITIVE
DEVICES
All ESD sensitive compon ents ar e solid state and a
symbol (Fig. 5) i s used to indica te this. When h an-
dling a ny component with t his sym bol, comply with
the following procedu res to reduce the possibilit y of
electrostat ic cha rge bu ild up on th e body and ina d-
vert ent discha rge into the com pon ent. If it is not
known whet her t he par t is ESD sen sitive, assume
that it is.
(1) Always touch a kn own good gr ound befor e han -
dling the part. This sh ould be repea ted while han-
dling t he part and mor e frequ ently aft er sliding
across a sea t, sitting down fr om a standing position,
or walkin g a distance.
(2) Avoid tou ching electrical terminals of the part,
unless instructed to do so by a written procedu re.
(3) When using a voltmeter, be sure to conn ect t he
ground lead first.
(4) Do not rem ove t he part form it ’s prot ective
pa cking u ntil it is time to insta ll the pa rt.
(5) Before rem ovin g the part from it’s pakage,
ground the pakage to a kn own good grou nd on the
vehicle.
TESTING FOR VOLTAGE POTENTIAL
(1) Connect the gr ound lead of a voltmet er to a
known good gr ound (Fig. 6).
(2) Connect the oth er lead of the voltmeter to the
selected test point . Th e vehicle ignition ma y need to
be turn ed ON t o ch eck volt age. Refer t o the appropri-
ate test procedur e.
TESTING FOR CONTINUITY
(1) Remove t he fuse for t he circuit being checked
or, disconnect the battery.
(2) Connect one lea d of t he ohmmeter to on e side
of the circu it being t ested (Fig. 7).
Fig. 4 Probing Tool
1 - SPECIAL TOOL 6801
2 - PROBING END
Fig. 5 ELECTROSTATIC DISCHARGE SYMBOL
VA 8W-01 WIRING DIAGRAM INFORMATION 8W - 01 - 7
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