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Home›Engines›Caterpillar 3500B

Caterpillar 3500B Engine

The Caterpillar 3500B is an engine. It powers generator sets from Caterpillar, including the PM3516.

Also known as: Caterpillar 3500B

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Engine specifications

Generator sets powered by this engine

1
Caterpillar PM3516

How to read your Caterpillar engine serial & model number →

Common problems

15
  • Voltage is out of range at the sensor connector.
    Fix: Check and correct the voltage between pin A and pin B for the suspect sensor. The supply voltage should reach 5.0 + 0.5 VDC for all analog sensors and 8.0 + 0.5 for all digital sensors.
  • Voltage is out of range at the connector.
    Fix: Check and correct the voltage on the sensor side of the wiring harness between pin A and pin B for the suspect sensor. The supply voltage should reach 5.0 + 0.5 VDC for all analog sensors and 8.0 + 0.5 for all digital sensors.
  • The signal voltage does not meet the expected range (0.2 to 4.5 VDC) for all analog sensors.
    Fix: Repair the connectors and/or wiring or replace the connectors and/or wiring.
  • The resistance through the harness is not less than 10 Ohms.
    Fix: Repair the connectors and/or wiring or replace the connectors and/or wiring.
  • The oil level is low
    Fix: Add oil
  • The fuel level is low
    Fix: Add fuel
  • The frequency reading does not meet the expected range (150 Hz to 1000 Hz) for all digital sensors.
    Fix: Temporarily replace the sensor. Verify that the repair eliminates the problem.
  • The ET does not show constant pressure or a 5 + 2 kPa (0.7 + 0.3 psi) drop in pressure when compared to the actual pressure.
    Fix: Check for leaks. If no leaks are found, there is an internal leak in the suspect pressure sensor. Replace the sensor and calibrate the sensor.
  • The digital supply voltage is not 8.0 + 0.5 VDC when measured between P1-35 (700-OR) and P1-29 (998-BR). Digital - 03 to 04
    Fix: Check the sensor connections and wiring.
  • The diagnostic code does not change from a FMI of 04 to an FMI of 03 when the suspect sensor signal wire is disconnected from the ECM. 04
    Fix: Replace the ECM.
  • The diagnostic code does not change from a FMI of 03 to an FMI of 04 when a jumper wire is installed between the ECM and the suspect sensor. 03
    Fix: Repair the connectors and/or wiring or replace the connectors and/or wiring.
  • The CID-FMI does not change from 04 to 03 when the suspect sensor is disconnected. 04 to 03
    Fix: Replace the suspect sensor. Verify that the repair eliminates the problem.
  • The CID-FMI does not change from 04 to 03 when the sensor signal wire is disconnected.
    Fix: Repair the connectors and/or wiring or replace the connectors and/or wiring.
  • The CID-FMI does not change from 03 to 04 when a jumper wire is installed between pin B and pin C at the suspect sensor connector. 03 to 04
    Fix: Temporarily connect a new sensor. Verify that the new sensor solves the problem before you permanently install the new sensor. Calibrate the sensor.
  • The analog supply voltage is not 5.0 + 0.5 VDC when measured between P1-36 (997-OR) and P1-30 (993-BR). Analog - 03 to 04
    Fix: Check the sensor connections and wiring.

Compiled from service & troubleshooting documentation across every generator set that uses the Caterpillar 3500B.

Service specifications

16
TypeItemValueUnitCondition
OtherDigital sensor duty cycle above 851 °C (1564 °F)80% to 90%%temperature above 851 °C (1564 °F)
OtherDigital sensor duty cycle below 49 °C (120 °F)10% to 21%%temperature below 49 °C (120 °F)
OtherDigital sensor duty cycle between 49 °C (120 °F) and 851 °C (1564 °F)22% to 88%%temperature between 49 °C (120 °F) and 851 °C (1564 °F)
OtherDigital sensor frequency reading between pin C and pin B150 to 1000Hzall digital sensors
PressurePressure drop shown on ET5 ± 2kPa0.7 ± 0.3 psi
PressureVacuum pulled on differential pressure gauge5 ± 2kPa0.7 ± 0.3 psi
ResistanceResistance between suspect sensor signal wire and supply voltage / return line / engine ground at ECM connectorgreater than 20,000OhmsECM connectors J1/P1 and J2/P2 and suspect sensor disconnected
ResistanceResistance through the harness (signal wire to supply, signal wire to return)less than 10OhmsECM connectors J1/P1 and J2/P2 and suspect sensor connector disconnected
TemperatureExhaust temperature reading with cold engine on ET30°C86 °F; engine cold
TemperatureTemperature reading variance when below 0 °C (32 °F)15°Ctemperature below 0 °C (32 °F); 59 °F
VoltageAnalog sensor signal voltage between pin C and pin B0.2 to 4.5VDCall analog sensors
VoltageAnalog sensor supply voltage (regulated by ECM)5.0 ± 0.5VDCall analog sensors
VoltageAnalog sensor supply voltage at ECM, P1-36 (997-OR) to P1-30 (993-BR)5.0 ± 0.5VDCECS ON, engine OFF
VoltageDigital sensor supply voltage (regulated by ECM)8.0 ± 0.5VDCall digital sensors
VoltageDigital sensor supply voltage at ECM, P1-35 (700-OR) to P1-29 (998-BR)8.0 ± 0.5VDCECS ON, engine OFF
VoltageSuspect analog sensor signal voltage at ECM connector P10.2 to 0.6VDCECS ON, engine OFF

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Recommended fluids

FluidGradeStandardAmbientCapacityNotes
CoolantCat DEACDiesel; 3,000 Service Hours or Three Years; annual S·O·SSM Level 2 coolant sampling and analysis
CoolantCat ELCDiesel; 12,000 Service Hours or Six Years; add Cat ELC Extender at 6,000 service hours or one half of service life; annual S·O·SSM Level 2 coolant sampling and analysis
CoolantCat NGECNatural Gas; 16,000 Service Hours or Three Years; use interval that occurs first
Engine oilCat NGEONatural Gas
Engine oilCat Arctic DEO SYN SAE 0W-30-40°C to 30°CEngine Crankcase; Industrial Engines
Engine oilCat DEO SYN SAE 5W-40-30°C to 50°CEngine Crankcase; Industrial Engines
Engine oilCat DEO SAE 10W-30-18°C to 40°CEngine Crankcase; Industrial Engines
Engine oilCat DEO SAE 15W-40-9°C to 50°CEngine Crankcase; Industrial Engines
GreaseCat Generator Set GreasePart Number 108-8611

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Procedures

12
Test Step 1. Check for Connector Damage diagnostic
  1. Turn the circuit breaker for the battery to the OFF position.
  2. Turn the ECS to the OFF position.
  3. Check connectors and wiring for damage, corrosion, abrasion and incorrect attachment.
Test Step 10. Create an Open Circuit at the Sensor Connector diagnostic

⚠ Disconnecting the Atmospheric Pressure Sensor will cause several sensor diagnostic codes to become active. Troubleshoot the original code.

  1. Turn the ECS to the OFF/RESET position.
  2. Disconnect the suspect sensor.
  3. Turn the ECS to the ON position, engine OFF.
  4. The CID-FMI should change from 04 to 03.
Test Step 11. Compare the Pressure or Temperature to the Actual Pressure or Temperature diagnostic

Tools: 6V-9130 Temperature Adapter, Vacuum pump test unit, Differential pressure gauge, ET (Electronic Technician)

  1. Turn the ECS to the OFF/RESET position.
  2. For temperature sensors install a 6V-9130 Temperature Adapter near the sensor and observe the reading.
  3. For pressure sensors disconnect, remove the sensor, connect it to the sensor connector.
  4. Connect the vacuum pump test unit and differential pressure gauge.
  5. Turn the ECS ON, engine OFF, and observe the barometric pressure reading.
  6. Pull 5 kPa (0.7 psi) of vacuum and compare ET and test kit readings.
Test Step 12. Install a Jumper Wire diagnostic

Tools: Jumper wire with socket terminals

  1. Connect the suspect sensor.
  2. Remove the suspect sensor signal wire and ground wire from the ECM.
  3. Use a wire with socket terminals to connect sensor signal and ground at the ECM.
  4. Turn the ECS ON, engine OFF.
  5. The CID-FMI should change from 03 to 04 when the jumper is in place.
Test Step 13. Create an Open at the ECM diagnostic

⚠ Disconnecting the Atmospheric Pressure Sensor will cause several sensor diagnostic codes to become active. Troubleshoot the original code.

  1. Turn the ECS to the OFF/RESET position.
  2. Disconnect the suspect sensor signal wire from the ECM connector.
  3. Turn the ECS ON, engine OFF.
  4. Check if the CID-FMI changed from 04 to 03.
Test Step 14. Check the Voltage at the Sensor Connector diagnostic
  1. Turn the ECS to the OFF/RESET position.
  2. Turn ECS ON, engine OFF; measure the analog sensor voltage between pin C and pin B.
  3. Turn ECS OFF/RESET then ON, engine OFF; measure frequency and duty cycle between pin C and pin B.
Test Step 15. Check for Shorts in the Wiring Harness diagnostic
  1. Turn the ECS to the OFF/RESET position.
  2. Disconnect ECM connector J1/P1, ECM connector J2/P2 and the suspect sensor.
  3. Measure resistance between signal wire and supply voltage at the ECM connector.
  4. Measure resistance between signal wire and sensor return line.
  5. Measure resistance between signal wire and engine ground.
  6. Reconnect all connectors.
Test Step 16. Check the Signal Frequency and the Duty Cycle at the Sensor Connector diagnostic
  1. Turn the ECS to the OFF/RESET position.
  2. Remove pin C from the sensor connector.
  3. Connect the main power.
  4. Measure frequency and duty cycle from pin C with reference to pin B.
  5. Turn the ECS to the OFF/RESET position.
Test Step 17. Check the Resistance through the Harness diagnostic

Tools: Suitable piece of wire

  1. Disconnect ECM connector J1/P1, ECM connector J2/P2 and the suspect sensor connector.
  2. Connect pin A to pin C with a wire and measure resistance to supply at ECM P1.
  3. Connect pin B to pin C with a wire and measure resistance to return line at ECM P1.
  4. Remove all wire shorts and reconnect all connectors.
Test Step 18. Check the Voltage at the ECM diagnostic

⚠ The status screen on the ET displays INVALID DATA when the ECM reads a signal that is out of range.

Tools: ET (Electronic Technician)

  1. Turn the ECS to the OFF/RESET position, then ON with engine OFF.
  2. Measure analog voltage between suspect sensor signal voltage and sensor return at ECM P1.
  3. Observe the sensor reading on the ET status screen.
  4. Turn ECS OFF/RESET, then ON with engine OFF.
  5. Measure frequency and duty cycle between digital sensor signal and return at ECM P1.
  6. Start the engine and observe the ET status screen.
Test Step 2. Check for Active Diagnostic Codes diagnostic

Tools: ET (Electronic Technician)

  1. Connect the ET.
  2. Turn the ECS to the ON position. The engine should be OFF.
  3. Wait for 15 seconds for the CID-FMI.
  4. Determine the FMI and check for 262-03/262-04 and 263-03/263-04.
Test Step 3. Check the Voltage at the Connector diagnostic
  1. Turn the ECS to the OFF/RESET position.
  2. Measure voltage on the sensor side of the wiring harness.
  3. Measure voltage between pin A and pin B for the suspect sensor.

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Common questions

Which generators use the Caterpillar 3500B engine?

The Caterpillar 3500B powers 1 generator set(s), including Caterpillar PM3516.

What is a common problem with the Caterpillar 3500B engine?

A commonly reported issue on generators using the Caterpillar 3500B is: Voltage is out of range at the sensor connector.. Fix: Check and correct the voltage between pin A and pin B for the suspect sensor. The supply voltage should reach 5.0 + 0.5 VDC for all analog sensors and 8.0 + 0.5 for all digital sensors..