Columbia ParCar Expediter EX21-24A, Service Manual

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Section 4 - Troubleshooting
4-4
VEHICLE DRIVES SLOWLY
▪
Check for all physical/visual signs of damage, low tire
pressure or jammed linkages.
▪
Check for brake drag by turning vehicle power off,
releasing parking brake, and attempting to roll vehicle a
short distance.
▪
Plug in the Handheld Calibrator and check 5.01, 6.01 and
7.01 for appropriate values (maximum speed settings).
While driving check speed incrementally at 14.01 on the
handset. Also check the encoder pull up resistor and
encoder connector.
▪
Perform step 2 in Troubleshooting with Handheld
Calibrator .
▪
Check for weak, discharged or damaged batteries, or poor connections.
VEHICLE DRIVES IN FORWARD OR REVERSE ONLY
▪
Perform step 4 in Troubleshooting with Handheld
Calibrator . Figure 4-8
VEHICLE DRIVES BUT OPERATION IS JERKY OR INCONSISTENT
▪
Check speed switch carefully with analog ohmmeter for gradual,
smooth resistance sweep.
▪
Check motor brushes. Replace if bad or worn (Figure 4-
8).
Call Columbia Technical Support if problem persists. Have the following
information ready:
- VIN
- Vehicle Checksum (19.15)
-
Direction of travel where the operation is “jerky”
- Speeds at which vehicle jerks.
VEHICLE POWER CUTS OUT
The fault for a vehicle that exhibits a cut out symptom can only be
diagnosed while the vehicle is in a fault condition.
New brushes are square cut .
Brushes will “seat - in” with a
slight curve