Chrysler Sebring 2004 Service Manual page 2895

HEATING & A/C
*BLOWER RUNS AT ONLY ONE SPEED - ATC —
TEST
4 Turn the ignition off.
Reconnect all previously disconnected components.
Connect the DRBIII Scope Input Cable CH7058, Cable-To-Probe Adapter CH7062,
and the Red (+) and Black (-) X1 Test Leads CH7030 to the DRBIII .
Select the following from the DRBIII menu: PEP Module Tools; Lab Scope; Live
Data; and Lab Scope.
Set the time to 0.4ms/Div.
Set the voltage range to +20.0v.
Set the Offset to 4.00v.
Set the Probe to X1.
Start the engine.
Turn Automatic Temperature Control on.
Using the Red (+) X1 Test Lead, back probe the Blower Motor Control circuit in the
Blower Power Module C1 harness connector.
Connect the Black (-) X1 Test Lead to ground.
NOTE: Over the Blower Motor Control circuit, the Blower Power Module
provides a battery supply voltage signal to the Body Control Module (BCM)
while the BCM provides a variable duty cycle ground based on input from
the blower control switch.
NOTE: When the blower control switch is set to Lo speed, the BCM provides
a short duty cycle (less time grounding the signal). As higher blower speeds
are requested, the BCM increases the duty cycle (more time grounding the
signal).
NOTE: When the blower control switch is set to High speed, the duty cycle
increases to where the signal pattern is a flat line on ground.
Set the blower control to LO speed and then slowly turn it to HI speed while
observing the DRBIII display.
The duty cycle pattern should change smoothly as the blower switch is turned from
Lo to High. The high part of the cycle will decrease as the blower speed increases.
Does the DRBIII display the signal as described above?
Yes → Replace the Blower Power Module in accordance with the Service
→ Replace and program the Body Control Module in accordance
No
ACTION
Information.
Perform BODY VERIFICATION TEST - VER 1.
with the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
Continued
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APPLICABILITY
All