Chassis Electrical System
Section
| General information | |
|---|---|
| 2 | Electrical troubleshooting - general information |
| 3 | Fuses and fusible links - general information |
| 4 | Circuit breakers - general information and check |
| 5 | Relays - general information and testing |
| 6 | Turn signal and hazard flashers - check and replacement |
| 7 | Steering column switches - replacement |
| 8 | Ignition switch and key lock cylinder- replacement |
| 9 | Instrument panel switches - replacement |
| 10 | Fuel, temperature and oil pressure gauges- check |
| 11 | Instrument cluster - removal and installation |
| 12 | Radio and speakers - removal and installation |
| 13 | Antenna - removal and installation |
| 14 | Headlight bulb - replacement |
| 15 | Headlights and fog lights- adjustment |
| 16 | Headlight housing - replacement |
| 17 | Bulb replacement |
| 18 | Wiper motor - replacement |
| 19 | Horn - check and replacement |
| 20 | Daytime Running Lights (DRL)- general information |
| 21 | Rear window defogger (SUV models) - check and repair |
| 22 | Cruise control sys.te~ - description and check |
| 23 | Power window system - description and check |
| 24 | Power door lock and keyless entry system - description and check |
| 25 | Electric side view mirrors - description and check |
| 26 | Power seats - description and check |
| 27 | Data Link Communication system - description |
| 28 | Airbag system - general information |
| 29 | Wiring diagrams- general information |
Table Caption: This table provides a comprehensive index of electrical system components and troubleshooting procedures for a vehicle, ranging from general information on fuses and relays to specific component replacement and system descriptions.
1 General information
**WARNING:
Refer to the Warning and Caution in Chapter 5, Section 1 under "Battery disconnection."
The electrical system is a 12-volt, negative ground type. Power for the lights and all electrical accessories is supplied by a lead/acid-type battery that is charged by the alternator.
This Chapter covers repair and service procedures for t11e vari› ous electrical components not associated with the engine. Informa› tion on the battery, alternator, distributor and starter motor can be
2 Electrical troubleshooting - gen. eral informatio. n
· Refer to illustrations 2.5a, 2.5b, 2.6, 2.9 and 2.15
A typical electrical circuit consists of an electrical component, any switches, relays, motors, fuses, fusible links or circuit breakers related to that component and the wiring and connectors that link the component to both the battery and the chassis. To help you pinpoint an electrical circuit problem, wiring diagrams are included at tt1e end of this Chapter.
Before tackling any troublesome electrical circuit, first study the appropriate wiring diagrams to get a complete understanding of what makes up that individual circuit. Trouble spots, for instance, can
found in Chapter 5.
It should be noted tha t whe n portions o f the e lectrica l s yste m are serviced, the negative cable should b e disconne cte d from the battery to prevent electrical shorts and/or fires.
** CAUTION:
•,
On models equipped with the Theftlock audio s y s tem, be sure the lockout feature is turned off before p erformin g any proce› dure which requires dis connecting the b attery (s ee the front of this manual).
• •
..
often be n a rrowed down by noting if othe r compo n e nts rela ted to the circuit are operating properly. If sev e ral compon e nts o r circuits fail at one time, chances are the problem is in a fuse or gro und connection, because several circuits a re ofte n routed thro u gh th e s ame fuse and ground connections.
Electrical problems u s ually ste m from simple cau s e s, such a s loose or corroded connections, a blown fuse, a m e lte d fusible link or a failed relay. Vi s ually inspect the c ondition of all fuses, wi res and conne ctions in a problem circuit before troubleshooting the c ircuit.
If tes t equipment and instruments are g oing to b e utiliz ed , use the diagrams to pla n ahead of time whe re y o u will m a l<e th e n ece ssary connections in order to accurately pinpoint the tro uble s pot.
The basic tools needed for e lectrica l troubl eshooting include a cir› cuit tester or voltmeter ( a 1 2-volt bulb with a set o f test lead s c a n also be used), a continuity tes ter, whic ll includes a bul b, batte ry and set of t e st leads, and a jumpe r wire, prefera bly with a circuit breaker incorpo› rated, which can be u s ed to bypass e lectri ca l c omponents (s ee illustra› tions). Before atte mpting to locate a problem with test instruments, use the wiring diagram(s ) to d ecide whe r e to m ake th e c onne ctions.
VOLTAGE CHECKS
Voltage che cks shou ld b e p e rforme d if a circuit is n o t fun c tioning properly. Conne ct one lead of a circuit tester to e ithe r th e n e gative battery terminal or a known good ground. Connect the othe r lea d to a
•
connector in the circuit b e ing tes ted, pre f e rably n eares t to the battery or fu s e ( s e e illus tratio n). If th e b u lb of the tester lights, voltage is present, which means tha t the p a rt of the circuit between the c onnector and the ba ttery is proble m free. C ontinue checking the rest of the circuit in the same fashion. When you reach a point at which no voltage is present, the problem lies b e tween tha t point a nd the las t test point with voltage. Most of the time the proble m can b e tra ced to a loose c onnection.
~"~~" Note: Keep in mind that some circuits receive voltage only when the ignition key is in the A ccessory or Run position.
FINDING A SHORT
One method of finding s horts in a circuit is to remove the fuse and connect a test light o r voltmeter in place of the fuse terminals . There should be no volta ge present in the circuit. Move the wiring
