ignition on. If scan tool does not display BUS SHORT TO 5 VOLTS,
replace CTM. If scan tool displays BUS SHORT TO 5 VOLTS, go to next
step.
8) Disconnect scan tool from DLC. Using external voltmeter,
measure voltage between ground and DLC connector terminal No. 3
(Violet/Brown wire). If voltage is more than 4 volts, repair
Violet/Brown wire for short to voltage. If voltage is 4 volts or less,
go to next step.
9) Measure voltage between ground and DLC connector terminal
No. 11 (White/Black wire). If voltage is more than 4 volts, repair
White/Black wire for short to voltage. If voltage is less than 4
volts, replace scan tool cable or scan tool as necessary.
10) Turn ignition off. Using external ohmmeter, measure
resistance between Powertrain Control Module (PCM) connector C3
terminal No. 30 (Violet/Brown wire) and connector C1 terminal No. 17
(Violet/Black wire). PCM is located at right inner fender. If
resistance is less than 800 ohms, repair short between Violet/Brown
wire and Violet/Black wire. If resistance is 800 ohms or more, go to
next step.
11) Measure resistance between PCM connector C3 terminal No.
28 (White/Black wire) and PCM connector C1 terminal No. 17
(Violet/Black wire). If resistance is less than 800 ohms, repair short\
between Violet/Black and White/Black wires of both connectors. See
wiring diagram for clarification. If resistance is 800 ohms or more,
replace PCM.
BUS SHORT TO BATTERY
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
VERIFICATION TEST VER-1 after each repair.
CAUTION: Always turn ignition off prior to disconnecting any module
connector.
1) Turn ignition off. Disconnect Powertrain Control Module
(PCM). PCM is mounted in right side of firewall. Turn ignition on. If
scan tool does not display BUS SHORT TO BATTERY, go to step 10). If
scan tool displays BUS SHORT TO BATTERY, go to next step.
2) Turn ignition off. Disconnect instrument cluster. Turn
ignition on. If scan tool does not display BUS SHORT TO BATTERY,
replace instrument cluster. If scan tool displays BUS SHORT TO
BATTERY, go to next step.
3) Turn ignition off. Disconnect compass mini-trip computer.
Turn ignition on. If scan tool does not display BUS SHORT TO BATTERY,
replace compass mini-trip computer. If scan tool displays BUS SHORT TO
BATTERY, go to next step.
4) Turn ignition off. Disconnect CCD radio. Turn ignition on.
If scan tool does not display BUS SHORT TO BATTERY, replace radio. If
scan tool displays BUS SHORT TO BATTERY, go to next step.
5) Turn ignition off and wait 2 minutes. Disconnect Air Bag
Control Module (ACM). ACM is located under center of instrument panel.\
Turn ignition on. If scan tool does not display BUS SHORT TO BATTERY,
replace ACM. If scan tool displays BUS SHORT TO BATTERY, go to next
step.
6) Turn ignition off. Disconnect Central Timer Module (CTM).\
CTM is located under left side of instrument panel. Turn ignition on.
If scan tool does not display BUS SHORT TO BATTERY, replace CTM. If
scan tool displays BUS SHORT TO BATTERY, go to next step.
7) Turn ignition off. Disconnect anti-lock brake controller
module. Controller module is mounted to top of ABS hydraulic unit.
Turn ignition on. If scan tool does not display BUS SHORT TO BATTERY,
replace anti-lock brake controller module. If scan tool displays BUS
SHORT TO BATTERY, go to next step.
8) Disconnect scan tool from DLC. Using external voltmeter,
measure voltage between ground and DLC connector terminal No. 3
(Violet/Brown wire). If voltage is more than .2 volt, repair
Violet/Brown wire for short to voltage. If voltage is .2 volt or less,
go to next step.
9) Measure voltage between ground and DLC connector terminal
No. 11 (White/Black wire). If voltage is more than .2 volt, repair
White/Black wire for short to voltage. If voltage is less than .2
volt, replace scan tool cable or scan tool as necessary.
10) Turn ignition off. Using external ohmmeter, measure
resistance between ground and Powertrain Control Module (PCM)
connector C1 terminal No. 31 (Black/Tan wire). PCM is located at right\
inner fender, at corner of firewall. If resistance is less than 10
ohms, go to next step. If resistance is 10 ohms or more, repair open
Black/Tan wire.
11) Measure resistance between ground and PCM connector C1
terminal No. 32 (Black/Tan wire). If resistance is less than 10 ohms,
replace PCM. If resistance is 5 ohms or more, repair open Black/Tan
wire.
BUS SHORT TO GROUND
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
VERIFICATION TEST VER-1 after each repair.
CAUTION: Always turn ignition off prior to disconnecting any module
connector.
1) Turn ignition off. Disconnect Powertrain Control Module
(PCM). PCM is mounted in right side of firewall. Turn ignition on. If
scan tool does not display BUS SHORT TO GROUND, replace PCM. If scan
tool displays BUS SHORT TO GROUND, go to next step.
2) Turn ignition off. Disconnect anti-lock brake controller
module. Controller module is mounted to top of ABS hydraulic unit.
Turn ignition on. If scan tool does not display BUS SHORT TO GROUND,
replace anti-lock brake controller module. If scan tool displays BUS
SHORT TO GROUND, go to next step.
3) Turn ignition off. Disconnect instrument cluster. Turn
ignition on. If scan tool does not display BUS SHORT TO GROUND,
replace instrument cluster circuit board. If scan tool displays BUS
SHORT TO GROUND, go to next step.
4) Turn ignition off. Disconnect compass mini-trip computer.
Turn ignition on. If scan tool does not display BUS SHORT TO GROUND,
replace compass mini-trip computer. If scan tool displays BUS SHORT TO
GROUND, go to next step.
5) Turn ignition off. Disconnect CCD radio. Turn ignition on.
If scan tool does not display BUS SHORT TO GROUND, replace radio. If
scan tool displays BUS SHORT TO GROUND, go to next step.
6) Turn ignition off and wait 2 minutes. Disconnect Air Bag
Control Module (ACM). ACM is located under center of instrument panel.\
Turn ignition on. If scan tool does not display BUS SHORT TO GROUND,
replace ACM. If scan tool displays BUS SHORT TO GROUND, go to next
step.
7) Turn ignition off. Disconnect Central Timer Module (CTM).\
CTM is located under left side of instrument panel. Turn ignition on.
If scan tool does not display BUS SHORT TO GROUND, replace CTM. If
scan tool displays BUS SHORT TO GROUND, go to next step.
8) Disconnect scan tool from DLC. Using external ohmmeter,
measure resistance between ground and DLC connector terminal No. 3
(Violet/Brown wire). If resistance is less than 700 ohms, repair
Violet/Brown wire for short to ground. If resistance is 700 ohms or
