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Alternator Output Check - 4JG2T Opel Monterey A

Engine Electrics ~175 words

Alternator Output, Check

Check can be performed with alternator installed on vehicle or on test stand.

.D. ICON11.tif0,750,75tiff;; Important!

If performing check using test stand, vacuum pump receives no lubrication; remove vacuum pump - see corresponding operation.

.D. ICON06.tif0,750,75tiff;; Inspect

Battery - fully charged.

Drive belt condition and tension - satisfactory.

Ground connections for alternator, engine, body, battery - satisfactory.

Battery terminal - tight, unbroken, not oxidised.
.D. ICON11.tif0,750,75tiff;; Important!

Do not reverse polarity of alternator terminals.

Do not short circuit alternator terminals.

Do not run alternator with battery disconnected (diodes may be destroyed).

Circuit diagram for alternator output check

1 Load resistor, variable

2 Battery

3 Voltmeter

4 Ammeter

5 Switch (starter key switch)

6 Charge telltale

7 Alternator

8 Charge relay
.P. C7197.tif97,5tiff;;
.D. ICON01.tif0,750,75tiff;; Remove, Disconnect

Ground cable from battery.

.D. ICON02.tif0,750,75tiff;; Install, Connect

Ammeter between terminal 'B' of alternator and cable to terminal 'B'.

Variable load resistor across battery terminals - ensure resistor set to maximum resistance.

Voltmeter across battery terminals.

Oscilloscope - in accordance with manufacturer's instructions.

Tachometer.

Ground cable to battery.

.D. ICON11.tif0,750,75tiff;; Important!
Do not set load resistor to minimum resistance at this stage.
.P. C7197.tif97,5tiff;;

Start engine or run alternator.

.D. ICON07.tif0,750,75tiff;; Measure

Current and voltage - 50 A at 5,000 rpm.

Adjust variable load resistor if required current is not attained.
.D. ICON06.tif0,750,75tiff;; Inspect

Voltage curves on oscilloscope - should be uniform.

If required current is not attained, or voltage curves appear as peaks and troughs, overhaul or replace alternator.
.P. C6227.tif97,5tiff;;