1999 DODGE RAM check engine

CURRENT WAVEFORM SAMPLES
EXAMPLE #1 - VOLTAGE CONTROLLED DRIVER
The waveform pattern shown in Fig. 4 indicate a normal
current waveform from a Ford 3.0L V6 VIN [U] engine. This voltage
controlled type circuit pulses the injectors in groups of three
injectors. Injectors No. 1, 3, and 5 are pulsed together and cylinders
2, 4, and 6 are pulsed together. The specification for an acceptable
bank resistance is 4.4 ohms. Using Ohm's Law and assuming a hot run
voltage of 14 volts, we determine that the bank would draw a current
of 3.2 amps.
However this is not the case because as the injector windings
become saturated, counter voltage is created which impedes the current
flow. This, coupled with the inherent resistance of the driver's
transistor, impedes the current flow even more. So, what is a known
good value for a dynamic current draw on a voltage controlled bank of
injectors? The waveform pattern shown below indicates a good parallel
injector current flow of 2 amps. See Fig. 4.
Note that if just one injector has a resistance problem and
partially shorts, the entire parallel bank that it belongs to will
draw more current. This can damage the injector driver.
The waveform pattern in Fig. 5 indicates this type of problem
with too much current flow. This is on other bank of injectors of the
same vehicle; the even side. Notice the Lab Scope is set on a one amp
per division scale. As you can see, the current is at an unacceptable
2.5 amps.
It is easy to find out which individual injector is at fault.
All you need to do is inductively clamp onto each individual injector
and compare them. To obtain a known-good value to compare against, we
used the good bank to capture the waveform in Fig. 6. Notice that it
limits current flow to 750 milliamps.
The waveform shown in Fig. 7 illustrates the problem injector
we found. This waveform indicates an unacceptable current draw of just
over one amp as compared to the 750 milliamp draw of the known-good
injector. A subsequent check with a DVOM found 8.2 ohms, which is
under the 12 ohm specification.
Fig. 4: Injector Bank w/Normal Current Flow - Current Pattern

EXAMPLE #2 - VOLTAGE CONTROLLED DRIVER
This time we will look at a GM 3.1L V6 VIN [T]. Fig. 8 shows
the 1, 3, 5 (odd) injector bank with the current waveform indicating
about a 2.6 amp draw at idle. This pattern, taken from a known good
vehicle, correctly stays at or below the maximum 2.6 amps current
range. Ideally, the current for each bank should be very close in
comparison.
Notice the small dimple on the current flow's rising edge.
This is the actual injector opening or what engineers refer to as the
"set point." For good idle quality, the set point should be uniform
between the banks.
When discussing Ohm's Law as it pertains to this parallel
circuit, consider that each injector has specified resistance of 12.2
ohms. Since all three injectors are in parallel the total resistance
of this parallel circuit drops to 4.1 ohms. Fourteen volts divided by
four ohms would pull a maximum of 3.4 amps on this bank of injectors.
However, as we discussed in EXAMPLE #1 above, other factors knock this
value down to roughly the 2.6 amp neighborhood.
Now we are going to take a look at the even bank of
injectors; injectors 2, 4, and 6. See Fig. 9. Notice this bank peaked
at 1.7 amps at idle as compared to the 2.6 amps peak of the odd bank (
Fig. 8 ). Current flow between even and odd injectors banks is not
uniform, yet it is not causing a driveability problem. That is because
it is still under the maximum amperage we figured out earlier. But be
aware this vehicle could develop a problem if the amperage flow
increases any more.
Checking the resistance of this even injector group with a
DVOM yielded 6.2 ohms, while the odd injector group in the previous
example read 4.1 ohms.
Fig. 8: Injector Odd Bank w/Normal Current Flow - Current Pattern

compartment.
* Inspect power window system ground circuit. See WIRING
DIAGRAMS.
RAM PICKUP
Inspect fuse No. 2 (30-amp) located in Power Distribution
Center (PDC). PDC is located in left side of engine compartment.
* Inspect circuit breaker No. 1 (20-amp) in fuse block. Fuse
block is located under left side of instrument panel.
* Inspect power window system ground circuit. See WIRING
DIAGRAMS.
RAM VAN & RAM WAGON
Inspect circuit breaker No. 20 (20-amp) in junction block.
Junction block is located in left end of instrument panel.
* Inspect fuse No. 12 (40-amp) in Power Distribution Center
(PDC). PDC is located in left side of engine compartment.
* Inspect power window system ground circuit. See WIRING
DIAGRAMS.
COMPONENT TESTS
CIRCUIT BREAKER
Dakota, Durango, Ram Pickup, Ram Van & Ram Wagon
1) Locate circuit breaker for power window system. See
TROUBLE SHOOTING. Pull circuit breaker out slightly, but ensure
circuit breaker terminals still contact terminals in fuse block.
2) Connect voltmeter negative lead to ground. Using voltmeter
positive lead, check both terminals of circuit breaker for battery
voltage. If voltmeter indicates battery voltage at both terminals,
circuit breaker is okay.
3) If voltmeter indicates battery voltage at one terminal
only, replace faulty circuit breaker. If voltmeter indicates no
voltage at either terminal, check for an open or shorted circuit to
circuit breaker. Repair as necessary and recheck system operation.
VENT WINDOW MOTOR
Caravan, Town & Country, & Voyager
1) Remove "D" pillar trim panel. See "D" PILLAR TRIM PANEL
under REMOVAL & INSTALLATION. Disconnect vent window motor connector.
Using jumper wires, apply battery voltage to vent window motor
terminals. Motor should rotate in one direction, moving window open or
closed. If window is in full closed or open position, no movement will
be observed and motor will make a grunting noise.
2) Reverse battery leads. Window should move in opposite
direction. If window does not move or window does not make a grunting
noise, replace vent window motor. If window moved completely open and
closed, motor should be reversed one more time to complete a full
window movement inspection.
3) If motor grunts and window does not move, remove motor
assembly. Check window motor crank for binding. Repair as necessary.
Recheck window operation. If window moves, check power window switch
continuity. See POWER WINDOW SWITCH. Replace switch as necessary. If
window switch is okay, check for open circuit between window motor and
window switch. See WIRING DIAGRAMS. Repair as necessary.