Testing the Electronic Control System
The following section defines how to test the ECM system.
Reading the Diagnostic Codes-Flash Method
The following steps describe using the flash method to interpret diagnostic codes:
- Ignition on.
- Toggle diagnostic switch for a period greater than 2.5 seconds.
- The blink code output sequence begins with a long blink followed by four groups of shorter blinks.
- If there are no fault codes stored, the Check Engine Light (CEL) will blink out code 4 4 4 4. This will appear as: long blink, pause, four short blinks, pause, four short blinks, pause, four short blinks, pause four short blinks. The cycle then repeats itself.
Note: Some applications may not use a vehicle speed sensor (VSS) and code 1133 will be logged for applications without a VSS. This flash code would not be considered a failure.
- If a fault code is stored, the code will be blinked out in the same way. (e.g. 1 2 1 1, fault in AGR control: long blink, pause, one short blink, pause, two short blinks, pause, one short blink, pause, one short blink). The cycle then repeats itself. Listed in Table
"Diagnostic Codes for the Turbotronic 638"
are the Turbotronic 638 diagnostic codes.
Engine Speed Sensor
Speed Sensor(Number One Instrumented Nozzle)
Battery Voltage to High (>20v)
Instrumented Injector(Number One Instrumented Injector)
Pedal Position Sensor
Water Temperature Sensor
Intake Air Temperature Sensor
Inlet Air Temperature Sensor
Fuel Temperature Sensor
Boost Pressure Sensor
Atmospheric Pressure Sensor
Air Mass Meter
Vehicle Speed Sensor
Air Gas Recirculator (AGR) Vacuum Modulator
Turbo Boost Vacuum Modulator
Glow Plug Relay
Timing Advance Actuator
Glow PlugTime Lamp/Diagnostic Lamp
Air Conditioning System
Redundant Shut-off Device
Brake Pedal Switches
Clutch Pedal Switch
Electric Fan Control
Fault in e2prom (EDC)
Lamp or Switch of Cruise Control
Main Relay in Wiring
Fuel Quantity Actuator(Injection Pump)
Fuel Quantity Regulator(Injection Pump)
Switched Key K15 (+12v)
Fuel Pump Potentiometer(Injector Pump)
Timing Advance Regulation
A/C Compressor Pressure
No Error in Memory
- To blink out the next code, toggle the diagnostic switch for a period greater than 2.5 seconds. Repeat until the code 0 0 0 0 is blinked out. This appears as a continuous series of long blinks, and indicates all codes have been blinked out.
- If the diagnostic switch is toggled again, the blink code is turned off.
- Switch ignition off.
- Ignition off.
- Toggle diagnostic switch.
- Switch on ignition and wait 2.5 seconds. Release diagnostic switch before 5 seconds has expired.
- Observe CEL and ensure 0 0 0 0 is blinked out.
- Toggle diagnostic switch for a period greater than 2.5 seconds and check that the blink code is turned off.
|Series 638 Service Manual - 6SE648|
|Generated on 10-13-2008|