Dodge Ram Truck 1500-2500-3500. Manual — part 1244

P0500-NO VEHICLE SPEED SIGNAL (CONTINUED)

3.

(B22) VEHICLE SPEED SENSOR SIGNAL CIRCUIT OPEN BETWEEN CAB AND PCM

Turn the ignition off.

Measure the resistance of the (B22) Vehicle Speed Signal circuit
between the PCM harness connector and the CAB Module harness
connector.

Is the resistance above 5.0 ohms?

Yes

>> Repair the open in the (B22) Vehicle Speed Signal circuit

between the CAB and PCM.

Perform POWERTRAIN VERIFICATION TEST. (Refer to 9
- ENGINE - STANDARD PROCEDURE)

No

>> Go To 4

4.

(B22) VEHICLE SPEED SENSOR SIGNAL CIRCUIT SHORT TO GROUND

Measure the resistance between ground and the (B22) Vehicle Speed
Signal circuit at the PCM harness connector.

Is the resistance below 100 ohms?

Yes

>> Repair the short to ground in the (B22) Vehicle Speed Sig-

nal circuit between the CAB and PCM.

Perform POWERTRAIN VERIFICATION TEST. (Refer to 9
- ENGINE - STANDARD PROCEDURE)

No

>> Go To 5

5.

PCM

NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal
push out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and
Ground circuits.

If there are no possible causes remaining, view repair.

Repair

Replace and program the Powertrain Control Module per Service Information.

Perform POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

9 - 1898

ENGINE - ELECTRICAL DIAGNOSTICS - SRT-10

DR/DH

P0505-IDLE AIR CONTROL MOTOR CIRCUITS

DR/DH

ENGINE - ELECTRICAL DIAGNOSTICS - SRT-10

9 - 1899

P0505-IDLE AIR CONTROL MOTOR CIRCUITS (CONTINUED)

For the Engine circuit diagram (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES/ENGINE CON-
TROL MODULE - SCHEMATIC - ELECTRICAL)

For a complete wiring diagram Refer to Section 8W.

•

When Monitored:
At power-up and battery voltage greater than 11.5 volts.

•

Set Condition:
The PCM senses a short to ground or battery voltage on any of the four Idle Air Control (IAC) driver circuits
for 100 ms while the IAC motor is active.

Possible Causes

(K40) IAC #1 DRIVER CIRCUIT SHORTED TO (K60) #2, (K39) #3, OR (K59) #4 IAC DRIVER CIRCUITS

(K60) IAC #2 DRIVER CIRCUIT SHORTED TO (K39) IAC #3 OR (K59) IAC #4

(K39) IAC #3 DRIVER CIRCUIT SHORTED TO (K59) IAC #4 DRIVER CIRCUIT

IAC DRIVER CIRCUIT SHORTED TO VOLTAGE

IAC DRIVER CIRCUIT SHORTED TO GROUND

IAC MOTOR

PCM

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)

1.

GOOD TRIP EQUAL TO ZERO

Ignition on, engine not running.

With the scan tool, read DTCs and record the related Freeze Frame data.

Is the Good Trip Counter displayed and equal to zero?

Yes

>> Go To 2

No

>> Refer to the INTERMITTENT CONDITION Symptom (Diagnostic Procedure).

Perform POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

9 - 1900

ENGINE - ELECTRICAL DIAGNOSTICS - SRT-10

DR/DH

P0505-IDLE AIR CONTROL MOTOR CIRCUITS (CONTINUED)

2.

IAC #1 DRIVER CIRCUIT SHORTED TO #2, #3, OR #4

Turn the ignition off.

Disconnect the IAC Motor harness connector.

Disconnect the C1 PCM harness connector.

NOTE: The following steps are checking for a short between the
IAC Driver circuits.
Measure the resistance between the (K40) IAC #1 Driver circuit and
#2, #3, #4 Driver circuits.

Is the resistance below 100 ohms on any of the Drivers?

Yes

>> Repair the short between the IAC Driver circuits.

Perform POWERTRAIN VERIFICATION TEST. (Refer to 9
- ENGINE - STANDARD PROCEDURE)

No

>> Go To 3

3.

(K60) IAC #2 DRIVER CIRCUIT SHORTED TO (K39) IAC #3 OR (K59) IAC #4 DRIVER CIRCUITS

NOTE: The following steps are checking for a short between the
IAC Driver circuits.
Measure the resistance between the (K60) IAC #2 Driver circuit and
(K39) IAC #3, (K59) IAC #4 Driver circuits.

Is the resistance below 100 ohms on any of the Drivers?

Yes

>> Repair the shorted between the IAC Driver circuits.

Perform POWERTRAIN VERIFICATION TEST. (Refer to 9
- ENGINE - STANDARD PROCEDURE)

No

>> Go To 4

DR/DH

ENGINE - ELECTRICAL DIAGNOSTICS - SRT-10

9 - 1901