Dashboard Warning Lights Are Lit (NIS0102AP)

Publication date: 1990-11-01
Reference number: NIS0102AP

DASHBOARD WARNING LIGHTS ARE LIT

TECHNICAL INFORMATION TIP

Reference Number(s): NIS0102AP, Date of Issue: November 1990

ALL DASHBOARD WARNING LIGHTS ARE LIT

YEAR(S): 1984-90

MANUFACTURER: Nissan

MODELS: 300ZX

DATE OF ISSUE: November 1990

ISSUE & TIP

A failed alternator diode or diodes can cause every warning light on the dashboard to light up on some Nissan 300ZXs. We've seen this problem most frequently on 1987 models. A quick check of the alternator's charging rate may give you the mistaken impression that the alternator is okay. And with replacement alternators as expensive as they are, it's important to be sure you've found the cause before condemning the alternator.

Use a charging system analyzer's diode test function to check the alternator diodes with the engine running. If you don't have a dedicated analyzer, use a DVOM to check for charging system alternating current (AC) leakage. Switch the DVOM to the AC voltage scale. Attach the positive DVOM lead to the alternator's B+ output terminal (not the battery positive terminal) and the negative lead to ground.

Start the engine and watch the DVOM. A good alternator should read less than 0.5 volts of AC leakage. Higher AC leakage caused by defective diodes can cause circuit feedback problems and may also damage sensitive electronic parts.

Courtesy of Import Service Magazine

with thanks to:

George Chaleff

Independent Automotive Sales and Service

New Windsor, NY

REFERENCE NUMBER

NIS0102AP

NOTE: This information has been obtained from sources generally believed to be reliable. Use your own judgment before relying on this data. Neither the suppliers of these Technical Information Tips, nor lemon-25 Repair Information Company, LLC, guarantees or assumes responsibility for data accuracy or completeness, nor is liability assumed by the suppliers of these Technical Information Tips or lemon-25 Repair Information Company, LLC, for any claims or damages resulting from the use of this information.