INTERMITTENT PARASITIC LOAD PROBLEMS
Intermittent parasitic load can occur because of a memory device that does not power down with ignition off. With an intermittent parasitic load, battery draw can be greater than 1.0 amp.
To find an intermittent problem requires that an ammeter and Disconnect Tool (J-38758) test switch be connected and left in the circuit. (Scheme 1) Road test vehicle. After road test, turn ignition off and remove key.
Monitor the milliamps scale for 15-20 minutes after ignition is turned off. This allows monitoring memory devices to determine if they time out and stop drawing memory current. The test switch is needed to protect ammeter when the vehicle is started.
Scheme 1
| Component | Normal Draw | Maximum Draw | Time-Out (Minutes) |
|---|---|---|---|
| Anti-Theft System | 0.4 | 1.0 | — |
| Auto Door Lock | 1.0 | 1.0 | — |
| Body Control Module | 3.6 | 12.4 | 20 |
| Central Processing System | 1.6 | 2.7 | 20 |
| Electronic Control Module | 5.6 | 10.0 | — |
| Electronic Level Control | 2.0 | 3.3 | 20 |
| Heated Windshield Module | 0.3 | 0.4 | — |
| HVAC Power Module | 1.0 | 1.0 | — |
| Illuminated Entry | 1.0 | 1.0 | 1 |
| Light Control Module | 0.5 | 1.0 | — |
| Oil Level Module | 0.1 | 0.1 | — |
| Multi-Function Chime | 1.0 | 1.0 | — |
| Pass Key Decoder Module | 0.75 | 1.0 | — |
| Power Control Module | 5.0 | 7.0 | — |
| Retained Accessory Power | 3.8 | 3.8 | — |
| Radio | 7.0 | 8.0 | 15 |
| Twilight Sentinel Module | 1.0 | 1.0 | — |
| Voltage Regulator | 1.4 | 2.0 | — |
GENERAL MOTORS PARASITIC LOAD
