Testing Ported EGR Valve on Honda Accord 1990-1993

1. Run Accord engine to operating temperature and allowit to idle. Attach a vacuum gauge to EGR vacuum hose. Locate EGR vacuum solenoid.
2. Using a jumper wire, ground signal wire from ECM to EGR vacuum solenoid. Vacuum should be present at EGR vacuum hose. On some models, engine speed may have to be increased 3000-4000 RPM.
3. Connect a vacuum pump to EGR valve. Start Accord engine. Apply vacuum to EGR valve. If engine runs rough or stalls, and gauge holds vacuum, EGR valve is functioning properly.

When discharging Honda Accord 1990-1993 air conditioning system, use only approved refrigerant recovery/recycling equipment. Make every attempt to avoid discharging refrigerant into the atmosphere.

Before disconnecting any lines or fittings, the system must be completely discharged using approved refrigerant recovery and recycling equipment.

Discharging AC System
Recent findings by the EPA indicate that R-11, R-12 and R-113 are harmful to the Earths’ protective Ozone layer. Make every attempt possible, to avoid discharging R-11, R-12 or R-113 into the atmosphere.

1. Remove service valve caps and install gauges. For high side gauge hose, Adapter (D81L-19703-A) mustbe used to connect to high side service valve.
2. Place open end of center hose in garage exhaust outlet or in a well ventilated area. Slightly open low sidegauge valve and let refrigerant escape slowly without loosing refrigerant oil.
3. When system is nearly discharged, using approved refrigerant recovery/recycling equipment, open highside gauge valve to release any pressure trapped in compressor. Close valves immediately after discharging to prevent entry of moisture.

Disconnecting Lines and Fittings
1. After system is discharged, using approved refrigerant recovery/recycling equipment, carefully clean entire area around coupling nut to prevent dirt entering system. Always use two wrenches to avoid twisting or distorting lines and fittings (hold fitting with one wrench while loosening coupling nut with second wrench).
2. Cap or plug all LINES and FITTINGS immediately to prevent entry of air and moisture into system. Do not remove these caps until connections are being made.

Component Replacement
When components are replaced, system oil level must be adjusted. Add refrigeration oil to replacement component.

Using R12 Refrigerant – Safety Precautions

1. Always work in a well-ventilated, clean area. Refrigerant (R-12) is heavier than oxygen, and will displace oxygen in a confined area. Always wear eye protection when working around air conditioning systems and R-12. The system’s high pressure can cause severe injury to eyes and skin if a hose were to burst. R- 12 evaporates quickly when exposed to atmosphere, freezing anything it contacts.
2. Use care when handling refrigerant containers. DO NOT drop or strike containers or expose refrigerant containers to excessive heat. Containers must never be heated more than 125°F (52°C). Never expose R-12 directly to open flame.

When R-12 is exposed to an open flame, drawn into a running engine, or detected with a Halide (propane) leak tester, poisonous phosgene gas is formed. Keep work areas ventilated and avoid running engines near work area.

Using Individual R12 Cans
Disposable refrigerant cans (referred to as one pound cans) have a flat type seal or a screw type seal, and proper can tap must be used for each type. Be sure sealing gasket on can tap is in good condition.

A proper safety can tap will prevent refrigerant from flowing back into open can, as tap has a one-way flow control.

Recent findings by the EPA indicate that R-11, R-12 and R-113 are harmful to the Earths’ protective Ozone layer. Make every attempt possible, to avoid discharging R-11, R-12 or R-113 into the atmosphere.

Multi-Can Dispensing Valves
A multi-can dispensing valve allows attachment of several cans of refrigerant, and is a good substitute when a bulk container is not available.

Cans are installed onto each leg of multi-can dispensing valve in the same manner as the individual cans, and each leg has its own can tap.

Can Tap Installation Flat Type Seal Cans
On cam-lock or one-piece can taps, first turn the handle outward to the fully open position. Securely engage locking lugs over the can flange, and lock them in place by turning cam lock or locking nut. Screw tap assembly into adapter so sealing gasket is fully seated against the can top.

Turn tap inward to pierce the can and close the tap. DO NOT open tap until ready to purge the service hose or dispense refrigerant into the system. On 2-piece can taps, be certain tap handle is turned fully inward to the closed position.

Check that locking base is turned to its outer limit. Securely engage locking lugs over the can flange. Turn entire tap assembly (without disturbing the closed setting) downward into the locking base to pierce the can. DO NOT open tap until ready to dispense into system.

Screw Type Seal Cans
Ensure can tap is fully closed. Screw refrigerant can into can tap fitting until tight. This will pierce the can. Connect tap to center hose on manifold gauge set. DO NOT open tap until ready to dispense R-12 into system.

DO NOT open high side hand valve while air conditioning system is in operation. This high pressure could rupture can or fitting at safety can valve, resulting in damage and personal injury.

Connecting Lines and Fittings
A new “O” ring should be used in all instances when connecting lines and fittings (dip “O” ring in clean refrigeration oil and make certain it is not twisted during installation). Always use two wrenches to avoid twisting or distorting lines and fittings, tighten coupling nuts securely.

Placing System in Operation
After component replacement and/or system servicing has been completed and all connections have been made, proceed as follows:

1. Evacuate the system using a vacuum pump.
2. Charge the system with new R-12 (refrigerant) according to each individual vehicle.
3. Leak test the system, with particular attention to all new connections and components.
4. Make a performance test of the system. Never assume that a recharging has automatically corrected a problem.

Compressor Removal Information – Isolation Method
On systems which have compressors equipped with stem-type service valves (Tecumseh), it is possible to isolate the compressor for removal.

Isolating
Turn both high and low pressure manual valves to extreme clockwise (front seat) position. Loosen cap on high pressure manual valve connection to compressor and allow gas to escape until compressor is relieved of pressure.

Compressor Removal Information – Discharge Method
This procedure is to be used on vehicles which have compressor equipped with Schrader service valves. In these cases, the compressor cannot be isolated and the system must be discharged, using approved refrigerant recovery/recycling equipment, prior to compressor removal.

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Some Honda Accord 1990-1993 models are equipped with a glass sun roof. This unit may also be referred to as a moon roof. Power sun roof is operated with ignition switch in “II” (ON) position.

Sun roof slides rearward on all Accord models. A permanent magnet type motor is used to operative a cable drive to open and close sun roof. If sun roof power drive fails, sun roof can be operated manually by using a socket inserted through access hole near drive motor.

Maintenance
Periodically, pour a small amount of water into drain rails at edges of sun roof to ensure drain tubes remain clear. Water should drop from drain tubes at rear of right front and left rear wheel wells.

Periodic lubrication is not required. When components are removed for repair or replacement, apply multipurpose grease lightly to all moving parts, except cables. Use molybdenum grease on cable assemblies.

Sun Roof Height
Roof panel should be even with glass weatherstrip within 0.02-0.06″ (0.5-1.5 mm). If adjustment is required in front, pry out rail holder cover and loosen nut. Install or remove shims between frame and sunshade rail holder.

If adjustment is required in rear, install or remove shims between guide rail and sunshade rail.

Wind Deflector
Open sun roof. Pry rail covers off both sides. Loosen mounting nuts. Adjust wind deflector forward or backward so deflector seal touches roof panel evenly across entire front edge.

Measure wind deflector height from top edge of deflector to roof panel at center of deflector. Wind deflector height should be 0.7″ (17 mm). Deflector arm cannot be adjusted. If arm or deflector is damaged, replace wind deflector assembly.

Function Test

1. Carefully pry sun roof switch/cruise control switch out of instrument panel. Unplug connectors from switches. Connect jumper wire between Green/Yellow wire and body ground. Turn ignition switch to “II” position. If sun roof opens, check switch. If sun roof does not open, check foe open in Green/Yellow wire. Repair or replace as necessary.
2. Connect jumper wire between Green/Red wire and body ground. Turn ignition switch to “II” position. If sun roof closes, check switch. If sun roof does not open, check foe open in Green/Red wire.
3. Using an ohmmeter, check for continuity between Black wire and body ground. If no continuity exists, check for open in Black wire. Repair as necessary.

Motor Test
Remove headliner. Unplug 2-pin connector from the motor. Using jumper wires, connect connector terminals to battery voltage and ground. Check for motor operation.

Reverse jumper wires and retest. Replace motor if it does not operation in both directions.

Relay Test
Sun roof system is equipped with separate relays for opening and closing functions. Remove sun roof relay from dash fuse/relay box. Test continuity with an ohmmeter.

Continuity should exist between terminals “B” and “C”. Using jumper wires, connect terminals “D” and “E” to battery voltage and ground. If continuity does not exist between terminals “A” and “C”, replace relay.

Switch Test
Carefully remove sun roof switch from instrument panel. Using an ohmmeter, check resistance of switch terminals with switch in indicated positions. If continuity is not as specified, replace switch.

TROUBLESHOOTING

All Honda Accord 1990-1993 models are equipped with Supplemental Restraint System (SRS). SRS wiring harness is routed close to instrument cluster, steering wheel, and related components.

All SRS wiring harnesses are covered by Yellow outer insulation. DO NOT use electrical test equipment on these circuits. Before working on steering column components, disable air bag system.

Ensure all component terminals and ground connections are clean and tight. Check possible faults in order listed. Repair or replace components and circuits as necessary.

Sun Roof Does Not Move but Motor Runs
Clutch out of adjustment. Foreign matter jammed in guide. Outer cable not properly attached.

Sun Roof Does Not Move & Motor Does Not Run (any switch)
Blown fuse No. 31 in under hood fuse/relay box. Blown No. 5 fuse in dash fuse box. Faulty sun roof motor. Faulty sun roof switch. Open in Green, Yellow/Green, Green/Yellow or Green/Red wire.

Sun Roof Does Not Move, Motor Does Not Run (Open Switch
Faulty OPEN relay. Faulty CLOSE relay. Faulty sun roof switch. Open in Green/Yellow or Green/Red wire.

Sun Roof Does Not Move, Motor Does Not Run (Clost Switch)
Faulty CLOSE relay. Faulty OPEN relay. Open in Green/Red or Green/Yellow wire.

REMOVAL & INSTALLATION

Drive Cables
Remove sun roof. Remove motor from sun roof frame. Remove guide rail mounting nuts. Lift off guide rails. If necessary, remove sun shade rail and drain seal from frame. Remove inner cables with sliders attached.

To install, reverse removal procedure.

Drive Motor
Remove headliner. Unplug motor harness connector. Remove mounting bolts and nuts. Remove motor. To install, reverse removal procedure.

Headliner
Remove sun visors, dome light, rear view mirror, pillar trim and grab handles. Remove rear seat and front passenger’s seat. Recline driver’s seat fully. Remove retaining clips. Taking care not to bend headliner, remove headliner starting at right rear corner. To install, reverse removal procedure.

Sun Roof

1. Open sun roof fully. Remove rail holder cover and rail holder. Remove sun shade rail holder, deflector, link stopper and lift-up guide. Slide sun roof forward using sun roof wrench. Remove front slider from rails.
2. Lift sun shade rail with guide rail. Support rail with small wooden block to provide clearance from rail bolt. Lift glass to remove link slider from inner cable slider. Slide glass from rails. Remove sun shade in same manner. To install, reverse removal procedure

Switch
Carefully pry switch panel from instrument panel. Unplug connectors from switches. Remove retaining screws (if equipped) and separate switch from panel. To install, reverse removal procedure.

Wind Deflector
Open sun roof fully. Pry up rail cover and rail holder cover. Remove sun shade rail stopper and link stopper. Remove wind deflector retaining nuts and remove wind deflector. To install, reverse removal procedure. Adjust wind deflector.

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Honda Accord 1990-1993 rear window defogger system uses a heating grid wire bonded to inside of window. Heat is regulated by a dash-mounted control switch with indicator light, relay and Integrated Control Unit (ICU).

Power is supplied to control switch through a fuse in fuse/relay box. On Accord and Prelude, ICU will supply power to grid for 25 minutes, or until ignition is turned off. On Civic, timer is located in rear window defogger switch.

Grid Filament Repair
Clean broken wire tips thoroughly. Place masking tape along both sides of broken wire. Apply Repair Paste (Dupont 4817) to broken section of grid.

Remove masking tape after paste has dried. Wait 24 hours before using defogger.

Defogger Switch Test
Carefully pry switch from instrument panel. Using an ohmmeter, ensure continuity exists between wire terminals “D” and “F” when control switch is pushed.

If continuity does not exist, replace switch. Continuity should exist between wire terminals “A” and “C” (indicator light), and wire terminals “B” and “E” (light) at all times.

Defogger Relay Test
Remove defogger relay. On Honda Accord and Prelude, relay is located in underdash fuse/relay box at left side kick panel.

On Honda Civic, relay is located in underhood fuse/relay box on right side of engine compartment.

Apply battery voltage to terminal “C”, and ground terminal “D”. See Fig. 3 . Use an ohmmeter to ensure continuity exists between terminals “A” and “B”. Ensure continuity does not exist between terminals “A” and “B” when battery voltage is removed.

Grid Filament Test

1. Turn ignition and rear window defogger on. Using a voltmeter, check for voltage between defogger positive wire terminal and body ground. If voltage is present, go to step 2). If voltage is not present, check for faulty defogger relay. Check for open in Black/Green defogger relay wire.
2. If voltage is present, use an ohmmeter to check for continuity between defogger negative wire terminal and body ground. If continuity does not exist, check for open in defogger ground wire. Connect voltmeter negative probe to defogger negative wire terminal. Connect voltmeter positive probe to center of each defogger grid wire.
3. If voltage is approximately 6 volts, defogger grid wire is okay. If voltage is greater than 6 volts, an open exists between center of defogger grid wire and negative side of center. If voltage is not present, an open exists between defogger grid wire and positive side of center. To locate break, move probe along grid wire until meter needle moves abruptly.

TROUBLESHOOTING

Defogger Inoperative
Check the following fuses: No. 1 (10-amp) and No. 8 (7.5-amp) in dash fuse/relay box (located at left kick panel). Check defogger timer circuit input (in ICU). Check for poor ground connections.

Check for short or open in Black/Green, Yellow/Black or Yellow/Green wires.

Indicator Light Inoperative (Defogger Operates)
On all Honda Accord 1990-1993 models, check for burned-out bulb. On Accord, check for short or open in Yellow/Black or Yellow/Green wires.

On Honda Civic and Prelude, check for short or open in Black/Yellow or Black wires.

Indicator Light Operates (Defogger Inoperative)
Check for blown fuse No. 17 (40-amp on Honda Accord coupe and sedan, 30-amp on wagon) in underhood fuse/relay box.

Check for poor ground connections. Perform defogger grid and defogger relay tests. Check for short or open in Yellow/Green or Yellow/Black wires.

Operation Time Too Long or Too Short

1. On Honda Accord and Prelude, check defogger timer circuit input (in ICU). On Honda Civic, check defogger timer circuit, located in defogger switch.
2. On Honda Accord, check for open or disconnected terminal in Yellow/Green or Yellow/Black wires. On Civic, check for open or disconnected terminal in Blue/Yellow, Black/Yellow or Black/Green wires. On Prelude, check for open or disconnected terminal in Yellow/White or Black/Green wires.

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