Engine Does Not Crank. Cadillac Eldorado 2000

For 1990-2009 cars only

Makes 🢒 Cadillac 🢒 2000 🢒 Eldorado 🢒 Engine 🢒 Engine Controls - 4.6L 🢒 Engine Does Not Crank

Engine Controls Component Views
PCM Power and Grounds
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The PCM controlled starter system consists of the following components:

•	The ignition switch

•	The Crank Request Circuit

•

The PCM

•	Internal mode switch (transaxle range / P/N) input

•	The crank relay

•	The starter solenoid

The PCM uses the starter relay to control the operation of the starter. With the ignition in the crank position, the PCM receives system voltage on the Crank Request Circuit. When the PCM senses the Crank Request input, the PCM checks that the right conditions exist to allow the operation of the starter. If the right conditions exist, the PCM turns ON the relay coil by applying ground to the control circuit. With the coil turned ON, the relay contacts close to apply voltage to the starter solenoid. As long as NONE of the following conditions are present, the PCM will allow the operation of the starter:

•	The engine is running.

•	The PCM does not receive a correct vehicle theft deterrent (VTD) password from the VTD system.

•	The vehicle operator attempts to crank the engine for an extended length of time.

•	The internal mode switch input indicates that the transaxle is not in PARK or NEUTRAL.

Diagnostic Aids

This diagnostic is intended to diagnose malfunctions in the non-PCM controlled portion of the starting system. To diagnose the PCM controlled portion of the system, refer to DTC P0615.

Ignition system DTCs set with the ignition switch in the START position if the starter relay or the starter is inoperative. When the PCM enables starter operation, the PCM also initiates the diagnostic test routines for DTCs P0335, P0340, and P0385. If a condition exists which prevents the engine from cranking, the PCM will not receive signal input from the CKP and/or the CMP sensor s, and the DTCs will set.

Check for the following conditions:

•	The condition of the battery.

The vehicle battery should be fully charged and load tested before proceeding with the starter diagnosis. If, during cranking, the battery voltage falls too low, a PCM reset will occur. The PCM will disable starter operation for the rest of the ignition cycle.

•	Poor connections at the following areas:

Refer to Wiring Repairs in Wiring Systems.

•

The PCM

•	The starter relay

•	The starter assembly

•	The transaxle connector

•	Ignition switch

•	Damaged harness

Inspect the wiring harness(es) and harness connectors for damage. If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Relay Terminal Identification

Use the underhood fuse block assembly and/or the rear fuse block assembly details, located in the Engine Controls Components Views, to determine the correct cavities to probe during diagnosis. Four blade relays can be inserted two ways. The number designations (i.e. 30, 85, 86, 87, and 87a) displayed in the relay details correspond directly to the cavity and NOT the numbering on the relay.

Step

Action

Values

Yes

Did you perform the Powertrain On Board Diagnostic (OBD) System Check?

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

Important: Check the battery connections.

Fully charge and load test the battery before proceeding with starter diagnosis. Refer to Diagnostic System Check - Engine Electrical in Engine Electrical.

Turn ON the ignition.
Observe the PRNDL display on the instrument panel.

Does the PRNDL indicate PARK?

Go to Step 3

Go to Powertrain On Board Diagnostic (OBD) System Check - Automatic Transmission

Inspect the OXY SEN 2 fuse for an open. Refer to Power Distribution Schematics in Wiring Systems.
If the fuse is open, locate and repair the cause of the open fuse. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 23

Go to Step 4

Turn ON the ignition, with the engine OFF.
Inspect for any of the following Powertrain DTCs:

•

DTC P0512

•

DTC P0615

•

DTC P1634

•

DTC P1631

Are any of these DTCs set?

Diagnose the applicable DTC. Go to Diagnostic Trouble Code (DTC) List/Type

Go to Step 5

Turn the ignition to Start.

Does the starter crank the engine?

Go to Diagnostic Aids

Go to Step 6

With the ignition in the START position, observe the 12 volt reference display on the scan tool.

Does the 12 volt reference display on the scan tool indicate OK?

Go to Step 8

Go to Step 7

Important: If the ignition 1 feed is shorted to ground, replace the related fuse.

Test the ignition 1 feed to the PCM for the following circuit conditions:

•	An open circuit

•	A short to ground

•	Poor terminal connections at the PCM

If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a problem found?

Go to Step 23

Go to Step 22

With the ignition in the START position, observe the Crank Request display on the scan tool.

Does the Crank Request display YES?

Go to Step 12

Go to Step 9

Turn OFF the ignition.
Disconnect the PCM connector.
Turn ON the ignition.
Connect test lamp between the Crank Request circuit and ground.
With the ignition in the START position, observe the test lamp.

Is the test lamp ON?

Go to Step 10

Go to Step 11

Check for poor terminal connections at the PCM.
If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a problem found?

Go to Step 23

Go to Step 22

Check for the following circuit conditions:

•	An open Crank Request circuit

•	Short to ground on the Crank Request circuit

•	Poor terminal connections at the ignition

If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a problem found?

Go to Step 23

Go to Steering Column Lock and Ignition Switch Cylinder Replacement - On Vehicle

Turn OFF the ignition.
Connect test lamp between the starter solenoid S terminal and ground.
Observe the test lamp with the ignition turned to the START position.

Is the test lamp ON?

Go to Diagnostic System Check - Engine Electrical

Go to Step 13

Check for an open batt1 maxifuse.

Is the fuse open?

Go to Step 14

Go to Step 16

Remove the start relay.
Check for a short to ground in the battery feed to the starter relay.
If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a problem found?

Go to Step 23

Go to Step 15

Leave the start relay disconnected.
Disconnect the starter solenoid circuit from the starter solenoid S terminal.
Check the starter solenoid circuit for a short to ground.
If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a problem found?

Go to Step 23

Go to Diagnostic System Check - Engine Electrical

Remove the start relay.
Connect test lamp to ground.
Probe the starter solenoid battery positive feed cavity in the relay connector.

Is the test lamp ON?

Go to Step 17

Go to Step 20

Leave the start relay disconnected.
Remove the fuel injector fuses.
Turn ON the ignition.
Using the appropriate jumper adapters, jumper the starter solenoid battery positive feed and starter solenoid circuit cavities in the relay connector.

Does the starter crank the engine?

Go to Step 18

Go to Step 19

Reinstall the fuel injector fuses.
Check for poor terminal connections in the start relay connector.
If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a problem found?

Go to Step 23

Go to Step 21

Check for the following circuit conditions: