DTC C1236 Low System Supply Voltage. Oldsmobile Intrigue 1999

For 1990-2009 cars only

Makes 🢒 Oldsmobile 🢒 1999 🢒 Intrigue 🢒 DTC 🢒 DTC C1236 Low System Supply Voltage

ABS Components
Antilock Brake System Schematics
Handling Electrostatic Discharge Sensitive Parts Notice
Data Link Connector Schematics
Power Distribution Schematics
Antilock Brake System Schematics

Circuit Description

DTC C1236 monitors the voltage level available to the EBTCM controller. If the voltage drops below 11.4 volts, full performance of the ABS system is not guaranteed. During ABS operation, there are several current requirements that will cause battery voltage at the EBTCM to drop. As a result, voltage is monitored prior to an ABS event to indicate good charging system condition. Voltage is also monitored during an ABS event when voltage may drop significantly.

Conditions for Setting the DTC

DTC C1236 can set only if the vehicle's speed is greater than 5 km/h (3 mph).

A malfunction exists if the switched battery voltage is less than 11.4 volts during a non-ABS event or less than 8.4 volts during an ABS event.

Action Taken When the DTC Sets

•	A malfunction DTC stores.

•	The ABS/ETS disables.

•	The amber ABS/ETS warning indicators turn on.

•	The red BRAKE warning indicator turns on if the rear piston in the ABS brake motor pack is not in the home position.

Conditions for Clearing the DTC

•	The condition responsible for setting the DTC no longer exists and the Scan Tool Clear DTCs function is used.

•	100 drive cycles pass with no DTCs detected.

Diagnostic Aids

Many conditions may cause an intermittent malfunction. Proper use of the scan tool enhanced diagnostic function can be used in order to measure the frequency of the fault. Thoroughly inspect any circuitry that may be causing the intermittent complaint for the following conditions:

•	Backed out terminals

•	Improper mating

•	Improperly formed or damaged terminals

•	Poor terminal-to-wiring connections

•	Rubbed-through wire insulation

•	A broken wire inside the insulation

If it is noted that only the ignition voltage drops below acceptable voltage levels after performing a Voltage Load test, inspect CKT 1339 for high resistance or an open condition.

Step

Action

Value(s)

Yes

Was the Diagnostic System Check performed?

Go to Step 2

Go to Diagnostic System Check - ABS

Install a scan tool.
Turn the ignition switch to the ON position.

Do not start the engine.

Select Snapshot on the scan tool.
Select Single DTC on the scan tool.
Enter C1236 on the scan tool.
Drive the vehicle at a speed above 5 km/h (3 mph).

Does DTC C1236 set as a current DTC?

Go to Charging System Check

Go to Step 3

Turn the ignition switch to the ON position.
Select Special Functions on the scan tool.
Use the scan tool in order to perform the Voltage Load test.

Are the ignition voltage and the battery voltage equal to or greater than the specified range?

10 V

Go to Step 4

Go to Charging System Check

Turn the ignition switch to the OFF position.
Disconnect the 24-way EBTCM connector C1.
Disconnect the 8-way EBTCM connector C2.
Disconnect the Electronic Brake Control Relay.
Use the J 39200 in order to measure the resistance between the Electronic Brake Control Relay harness connector terminal A2 and the 8-way EBTCM connector C2 terminal C.

Is the resistance within the specified range?

0-2 ohms

Go to Step 5

Go to Step 9

Disconnect the negative battery cable.
Disconnect the positive battery cable.
Use the J 39200 in order to measure the resistance between the positive battery terminal and the Electronic Brake Control Relay Harness connector terminal C1.

Is the resistance within the specified range?

0-2 ohms

Go to Step 6

Go to Step 10

Remove the fuse block ABS/ETS Fuse (10A).
Use the J 39200 in order to measure the resistance between the fuse block terminal C2 (ABS/ETS Fuse [10A]) and the 24-way EBTCM connector C1 terminal A9.

Is the resistance within the specified range?

0-2 ohms

Go to Step 7

Go to Step 11

Inspect the following components:

•	The Electronic Brake Control Relay harness connector

•	The 24-way EBTCM connector C1

•	The 8-way EBTCM connector C2

•	The positive battery cable connections

•	The negative battery cable connections

Inspect the above components for the following conditions:

•	Terminal damage

•	Poor terminal contact

•	Terminal corrosion

•	The above conditions may cause an open circuit.

Are there signs of terminal damage, poor terminal contact, or terminal corrosion?

Go to Step 12

Go to Step 8

Reconnect the 24-way EBTCM connector C1.
Reconnect the 8-way EBTCM connector C2.
Reconnect the Electronic Brake Control Relay.
Reconnect the positive battery cable.
Reconnect the negative battery cable.
Drive the vehicle at a speed above 5 km/h (3 mph).

Does DTC C1236 set as a current DTC?

Go to Step 13

Go to Step 14

Repair the open or high resistance in CKT 1633.

Is the repair complete?

Go to Diagnostic System Check - ABS

Repair the open or high resistance in CKT 102.

Is the repair complete?

Go to Diagnostic System Check - ABS

Repair the open or high resistance in CKT 1339.

Is the repair complete?

Go to Diagnostic System Check - ABS

Replace all of the terminals or the connectors that exhibit signs of poor terminal contact, corrosion, or damaged terminals.

Is the repair complete?

Go to Diagnostic System Check - ABS

Replace the EBTCM. Refer to Electronic Brake Control Relay Replacement .

Is the repair complete?

Go to Diagnostic System Check - ABS

Is the malfunction intermittent or is not present at this time?

Go to Diagnostic Aids