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E LECTRIC AL SYSTEM D IA G N O S T I C CHART
BLOW ER M O TO R IN O P E R A T IV E
A T H IG H SPEED O N L Y
(C-K F O U R -SEA SO N SY S T E M )
Check
in -lin e fuse
FUSE B LO W N
| F U S E O K |
C onn ect Teste r. Use to check
w ire fro m ju n c tio n to b lo w e r
relay to locate s h o rt. R epair
s h o rt c irc u it as .re q u ire d .*
W ith ig n itio n sw itch in the
" R u n " p o s itio n and the
heater o r A /C on, m ove the
blo w e r speed sw itch to H i.
Relay " c lic k " should be
heard when sw itch is m ove d.
CL ICK H E A R D
I
1
Check w ire te rm in a l on relay
th a t goes to ju n c tio n b lo c k
w ith 12 v o lt te st lam p.
X
I NO C L IC K H E A R D !
_
I
'
Check relay c o il c o n n e c to r
w ith 12 v o lt te s t lig h t.
LA M P L IG H T S
Replace b lo w e r
relay.
|L A M P D O ES N O T L IG H T |
j
LA M P L IG H T S | | lA M P D O ES N O T L IG H T |
___ _ 1
1
f—*
R epair open in w ire
1
Check w ire te rm in a l on b lo w e r
fro m ju n c tio n b lo c k
Check ground
speed sw itch c o n n e c to r w ith
to relay.
on relay
12 v o lt test lig h t.
|G R O U N D O K | |
b a d
g r o u n d
|
R eplace relay
R epair ground
r
i
|L A M P L IG H T S |
L A M P D O ES
N O T L IG H T
1
1
R epair open
in w ire fro m
b lo w e r speed
sw itch to relay.
Replace
B lo w e r speed
sw itc h .
C O M PRESSO R C LU T C H IN O P E R A T IV E 1
X
Check fuse
... 1
FUSE B LO W N
W ith ig n itio n sw itch in " R u n ” p o s itio n , and
A /C
" O n " , co nn ect
tester and lo cate s h o rt in one o f the fo llo w in g w ires o r c o m p o
nents. Replace a sh orted w ire o r d e fe ctive sw itch .
C-K
M O D E L S Y S T E M S
1.
W ire fro m fuse panel to m aster sw itc h (on c o n tro l).
2.
Master sw itch .
3.
W ire fro m m aster sw itch to th e rm o s ta tic sw itch .
4.
T h e rm o s ta tic sw itc h .
5. W ire fro m th e rm o s ta tic sw itch to discharge pressure sw itch .
6. Discharge pressure sw itch .
7. W ire fro m discharge pressure sw itch to com p ressor clu tc h
solenoid.
G M O D E L SY S T E M S
1. W ire fro m fuse panel to b lo w e r sw itc h .
2.
B low e r sw itch .
3.
W ire fro m b lo w e r sw itch to th e rm o s ta tic sw itch .
4.
T h e rm o s ta tic sw itc h .
5. W ire fro m th e rm o s ta tic sw itch to th e rm a l fuse.
6. T herm al fuse.
7. W ire fro m th e rm a l fuse to com pressor c lu tc h so le n o id .
M O T O R H O M E U N IT
1. W ire fro m fuse panel to b lo w e r sw itc h .
2.
B lo w e r sw itch .
3.
W ire fro m b lo w e r sw itch to th e rm o s ta tic sw itch .
4.
T h e rm o s ta tic sw itch .
5. W ire fro m th e rm o s ta tic sw itch to com p ressor clu tc h
solenoid.
[ FUSE O K |
Check C om pressor S o le n o id G round
|P O O R OR NO G R O U N D l
( G R O U N D
0~iT|
Repair g rou nd
D isco nnect c o n n e cto r on
com pressor clu tc h solen oid
and a p p ly 12 v o lts to so len oid.
X
NO C L IC K H E A R D
Replace solen oid
C L IC K H E A R D
W ith ig n itio n sw itc h in " R u n " p o s itio n and A /C " O n " , check
fo r d e fe ctive sw itc h at the fo llo w in g lo ca tio n s. Using an exte rn a l
ju m p e r w ire , d isco n n e ct the ele ctrica l lead at the sw itc h and
ju m p the sw itc h te rm in a ls (see "W irin g D ia g ra m s").
C-K M O D E L S Y S T E M
1. M aster S w itc h .
2. T h e rm o s ta tic S w itc h .
3. Discharge Pressure S w itch .
G M O D E L S Y S T E M
1. B lo w e r sw itch .
2. T h e rm o s ta tic S w itch .
3 . T h erm al fuse (See " L o w R e frig e ra n t Charge P ro te c tio n System
D iagn osis").
M O T O R H O M E U N IT
1. B lo w e r sw itc h .
2. T h e rm o s ta tic sw itch .
N O T E : If th e com pressor is s till in o p e ra tiv e a fte r the above
checks, check fo r pow e r feed at each co m p o n e n t since
tw o or m ore co m p o n e n ts are d e fe ctive or there is an
open in th e w ires c o n n e ctin g the co m p o n e n ts.
* S h o rt c irc u it m ay be in te rm itte n t.
If tester does n o t in d ic a te a s h o rt c irc u it,
m ove harness aro u n d as m u ch as possible
to re-create s h o rt c irc u it. W atch and
listen fo r arcing.
* * R e fe r to W iring Diagrams w hile performing
the follow ing checks.
Fig. 103-Electrical System Diagnosis Chart
1A
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Summary of Contents for Light Duty Truck 1973
Page 1: ......
Page 4: ......
Page 6: ......
Page 53: ...HEATER AND AIR CONDITIONING 1A 27 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 115: ...LIGHT DUTY TRUCK SERVICE M A N U A L HEATER AND AIR CONDITIONING 1A 89...
Page 123: ...BODY 1B 3 Fig 6 Typical 06 Van LIGHT DUTY TRUCK SERVICE MANUAL...
Page 149: ...BODY 1B 29 Fig 84 Body Mounting 06 Fig 85 Body Mounting 14 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 171: ...LIGHT DUTY TRUCK SERVICE M A N U A L Fig 2 Frame Horizontal Checking Typical FRAME 2 3...
Page 173: ...LIGHT DUTY TRUCK SERVICE M A N U A L Fig 4 10 30 Series Truck Frame FRAME 2 5...
Page 174: ...2 6 FRAME LIGHT DUTY TRUCK SERVICE MANUAL Fig 5 Underbody Reference Points G Van...
Page 185: ...FRONT SUSPENSION 3 11 Fig 16 Toe out on Turns LIGHT DUTY TRUCK SERVICE MANUAL...
Page 224: ......
Page 266: ......
Page 351: ...ENGINE 6 15 Fig ID Sectional View of Eight Cylinder Engine LIGHT DUTY TRUCK SERVICE MANUAL...
Page 375: ...EN G IN E 6 39 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 376: ...6 4 0 ENGINE LIGHT DUTY TRUCK SERVICE MANUAL...
Page 377: ...ENG IN E 6 41 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 378: ...LIGHT DUTY TRUCK SERVICE MANUAL Fig 37L K Series Engine Front Mount 6 42 ENG INE...
Page 400: ...6 6 4 ENG INE LIGHT DUTY TRUCK SERVICE MANUAL...
Page 401: ...ENG IN E 6 65 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 402: ...6 6 6 ENGINE LIGHT DUTY TRUCK SERVICE MANUAL...
Page 403: ...E NG IN E 6 67 Fig 36V C Series Engine Mounts LIGHT DUTY TRUCK SERVICE MANUAL...
Page 410: ......
Page 423: ...EN G IN E C OOLING 6K 13 Fig 16 Overheating Chart LIGHT DUTY TRUCK SERVICE MANUAL...
Page 424: ...6 K 1 4 ENG INE COOLING Fig 17 Coolant Loss Chart LIGHT DUTY TRUCK SERVICE MANUAL...
Page 456: ...6M 32 ENGINE FUEL Fig K15 Accelerator Controls G Van L 6 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 492: ......
Page 512: ...Fig 18e Vacuum Advance Diagram V8 Engine...
Page 516: ...6 T 2 4 E M IS S IO N CONTROL SYSTEMS LIGHT DUTY TRUCK SERVICE MANUAL...
Page 528: ......
Page 590: ......
Page 593: ...CLUTCHES MANUAL TRANSMISSIONS 7M 3 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 598: ...7M 8 CLUTCHES MANUAL TRANSMISSIONS LIGHT DUTY TRUCK SERVICE MANUAL...
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Page 654: ......
Page 743: ...FUEL TANKS AND EXHAUST 8 13 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 744: ...8 14 FUEL TANKS AND EXHAUST LIGHT DUTY TRUCK SERVICE MANUAL...
Page 760: ...8 30 FUEL TANKS AND EXHAUST Fig 40 Exhaust Pipe P Models LIGHT DUTY TRUCK SERVICE MANUAL...
Page 761: ...FUEL TANKS AND EXHAUST 8 31 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 763: ...FUEL TANKS AND EXHAUST 8 33 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 766: ......
Page 832: ...LIGHT DUTY TRUCK SERVICE MANUAL Fig 106 Power Steering Pump Mounting Typical 9 66 STEERING...
Page 833: ...PUMP ASSEMBLY STEERING GEAR TYPICAL SMALL V8 TYPICAL LARGE V8 STEERING 9 67...
Page 861: ...STEERING 9 95 Fig 134 Power Steering Pump Leakage LIGHT DUTY TRUCK SERVICE MANUAL...
Page 864: ......
Page 876: ......
Page 886: ...11 10 CHASSIS SHEET METAL LIGHT DUTY TRUCK SERVICE MANUAL...
Page 891: ...ELECTRICAL BODY AND CHASSIS 12 5 LIGHT DUTY TRUCK SERVICE MANUAL...
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Page 976: ...V...
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