| Table 1: | Side One Contains |
The diagnostic test tape will assist in the following diagnostic procedures:
SPEAKER/AMPLIFIER DIAGNOSTICS | |
|---|---|
Bass/Subwoofer test | 50 Hz sine tone |
Midrange speaker tests | 500 Hz warble tone |
Door tweeter test | 9k Hz spectral tone |
All speaker test | Combination tone |
Speaker buzz and rattle test | 50 Hz to 8k Hz swept sine (2 swept sine signals used at different sweep rates) |
CASSETTE TAPE DIAGNOSTICS AND INFORMATION | |
|---|---|
Tape motor speed test | Timed section in tape |
Instructions on tape head cleaning procedures | -- |
Important: On-Board Diagnostics, Test Tone Mode also tests the speakers one at a time at 100 Hz and at 3k Hz.
The speaker/amplifier and cassette tape diagnostics and information are followed by 4 song selections which are intended to be used in conjunction with the Audio System Diagnostic Charts for proper system operation.
Side Two Contains
Six song selections followed by:
NOISE RELATED PERFORMANCE DIAGNOSTICS | |
|---|---|
Noise diagnostics | Dead space |
Speaker/Amplifier Diagnostics
Always compare the front speakers to front, and rear speakers to rear. Do not compare front speaker to rear speaker because they could be different speakers or their mounting environment could cause them to sound different.
The 3 basic tones used to test and evaluate coaxial speakers, or other complex speaker systems, are a 50 Hz sine tone, 500 Hz warble tone, and a 9k Hz spectral tone. The combination tone is a blend of the above three tones.
Bass Speaker Test
The 50 Hz tone is used to evaluate the bass response of an audio system. This tone is also helpful in evaluating audio systems which have separate subwoofer amplifiers and speakers.
Midrange Speaker Test
The 500 Hz warble tone is used for the evaluation of midrange speaker response. This tone is qualified as a warble tone because it has different audio characteristics than a sine tone. This tone produces a warble sound. At these midrange frequencies, it is better to use a warble tone than a sine wave because the location of warble tone source, such as a speaker, is easier to identify. A normal sine tone can set up a standing wave within a vehicle which can make it difficult to determine its source location.
Tweeter Test
The 8.5k-9.5k Hz spectral tone is used for tweeter or high frequency evaluation. This tone is a section of frequencies of equal amplitudes ranging from 8.5k-9.5k Hz. This sounds like a group of crickets chirping. This type of tone is used for 2 reasons. One, much like the warble tone, it is easy to locate it's source, and two, this type of tone is easier to identify for those people with high end hearing loss problems.
All Speaker Test
The combination tone can be tested using a portion of the test tape and can also be used for numerous audio problems such as distorted or no sound from one or more speakers. When using the combination tone, comparative AC voltage measurements can be made on the speaker terminals, provided the fade and balance controls are in the detent position. With these voltage measurements, a determination can be made in the diagnosis of the speaker or amplifier.
Speaker and Grill Rattle Diagnostics
The next portion of the tape can be used to diagnose speaker and grill rattles. If the problem has already been isolated, the fade and balance controls can be set to the proper location and the test tones can be played in the specific problem area.
Cassette Tape Diagnostics and Information
Motor Speed
There is a 2 minute time period marked in this section of tape for the purpose of checking the cassette tape motor speed. This portion of the diagnostic tape can be used to verify or resolve problems when a customer complains that the audio from the cassette tape sounds abnormal. In some cases, improper tape motor speed can cause audio abnormalities. If the time taken for this test is between 1 minute and 56 seconds to 2 minutes and 1 second, the tape motor speed is within tolerance.
Cassette Tape Player Cleaning and Tape Care
Cassette players are very susceptible to dirt and magnetized equipment. The following should be inspected as part of any diagnosis:
| • | Cleanliness of the capstan, the small wheel inside the radio that supports the tape, and the head. Since both can be reached through the tape door, they should be cleaned before proceeding with any problem diagnosis. |
| • | To clean the head and capstan, a cassette tape cleaning cartridge is included with the Saturn SA9412G Diagnostic Tape/Tape Head Cleaning Kit. |
| • | If the head is magnetized, every tape played in the player will be degraded or possibly erased. |
| • | Cassette length. Tapes over 90 minutes in length, both sides total, are too thin for this equipment and could become jammed, torn, or cause damage to the equipment. |
Cassette Tape Player Cleaning
As stated in the Saturn Owner's Handbook, Saturn cassette players have a CLEAN indicator on the display which activates after approximately 30 hours of tape operation. The recommended cassette tape cleaning cartridge is a scrubbing type tape head cleaning cartridge. The preferred tape head cleaner and cleaning solution refill is available as part of the Audio System Diagnostic Kit. It is also recommended that the tape head cleaner be replaced if the felt pads appear soiled and worn.
When using the scrubbing type tape head cleaning cartridge, the following procedure should be used:
- Apply 2 drops of cleaning solution, included with cassette tape cleaning cartridge, to each felt pad (1) on the tape head cleaning cartridge.
- Insert cleaning cartridge into cassette tape player.
- Play cleaning cartridge for 30 seconds.
- Press the SIDE button and play the other side of the cleaning cartridge for 30 seconds.
- With the cleaning cartridge in the cassette tape player, press and hold the EJ (Tape Eject) button for 5 seconds to reset the CLEAN indicator.
- Remove cleaning cartridge and store in original package to prevent contamination or damage.
- Allow at least 3 minutes to dry after cleaning before using cassette tape player.
