Last post on May 31, 2013 at 7:44 PM
You are in the Isuzu Rodeo
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Isuzu Rodeo, Honda Passport, SUV
#1955 of 2305 Re: 92 & 2000 Isuzu rodeo EGR flow [atfdmike]-getting diagnostic codes?
May 17, 2006 (8:17 pm)
I believe the tech II tool referred to is also known as an OBD II computer diagnostic tool? I have a 92(OBD I) that I just needed to find the 12-pin harness to check for codes....still can't find it. the repair manual said under driver dash and to left. It said I could use a paper clip in pins A & B to trigger diagnostic codes on check engine dash light. This is done with suv NOT started but key power on.... I would verify this if I could find the electrical pin harness....any ideas?
May 18, 2006 (5:20 am)
I think you are correct....GM call it the Tech II, but OBDII is probably the same.
1992 Isuzu Truck Rodeo (2WD) V6-3137cc 3.1L (CPC)
Vehicle Level Powertrain Management Computers and Control Systems Testing and Inspection Displaying & Reading Trouble Codes
Displaying & Reading Trouble Codes
If a problem develops in a monitored system with the engine running, the "Check Engine" light will come "ON" and a trouble code will be stored in ECM memory. As long as a problem is present, the light will remain "ON" while the engine is running. If the problem is intermittent, the light will go out but a trouble code will be stored in ECM memory. As a bulb check, the "Check Engine" light will come "ON" with the ignition switched "ON" and the engine not running. If no codes are present, the light will go out upon starting the engine. If the light remains "ON," the system has detected a fault. To allow checking circuits which may be difficult to energize without driving the vehicle and being under particular operating conditions, all ECM controlled relays and solenoids (except fuel pump relay) are energized in Diagnostic mode.
Note that many electronic engine control tests require the use of a "Scan" tool.
Field Service Mode
If the diagnostic terminal is grounded with the engine running, the system enters Field Service mode and the "Check Engine" light will indicate whether it is in "Open Loop" or "Closed Loop." In "Open Loop," the light flashes two and one half times per second. In "Closed Loop," the light flashes once per second. If the system is running lean while in "Closed Loop," the light will stay "OFF" most of the time. Conversely, it will stay "ON" most of the time if the system is running rich. While in Field Service mode, the ECM will not store new trouble codes.
Extracting Trouble Codes
The "Check Engine" light displays trouble codes that are stored in ECM memory. To activate the Diagnostic mode, a special connector located in the center console is utilized. There is a conflict in the manual on this, as it also says it is located where you have looked previously. When the ALDL (assembly line diagnostic link) connector is jumpered between terminals "A" and "B" with the ignition "ON" and the engine not running, the light will flash any stored codes.
Here is diagram of aldl: http://www.carspace.com/atfdmike/.59a46397!v=
The first code to display should be code 12. This indicates that the self-diagnostics are functioning and is not a trouble code. The code 12 display is a flash followed by a short pause, then two flashes followed by a longer pause. If other codes are present, they will display in the same manner after code 12 has flashed three times. For example, the code 23 display is two flashes followed by a short pause, then three flashes followed by a longer pause. Each stored code is displayed three times, starting with the lowest in numerical order. Code 12 will repeat when all codes have shown. If no codes are stored, code 12 will display repeatedly until Diagnostic mode is exited by removal of the ALDL jumper wire. Remove the jumper wire before attempting to start the engine.
INTERMITTENT "CHECK ENGINE" LIGHT
"Intermittent" means that the "Check Engine" light may come on at times but does not stay on. Since codes may or may not be stored, the use of diagnostic charts could result in replacement of good parts.
Most intermittent problems are caused by faulty electrical wiring or connections. Carefully check these potential causes:
Poor mating of connector halves or terminals not fully seated in connector body.
Deformed or damaged terminals. All connector terminals in problem circuit should be carefully reformed to increase contact tension.
Poor terminal-to-wire connection. This requires removing terminal from connector body to properly check.
Poor ground connections.
If a visual check does not find the source of the problem, the vehicle may be driven with a voltmeter connected to a suspect circuit. An abnormal voltage reading when the problem occurs indicates the problem may be in that circuit. If wiring and connectors check okay and a code was stored for a circuit having a sensor (except codes 44 and 45), substitute a known good sensor and recheck.
Loss of ECM trouble code memory. To check, disconnect throttle position sensor and idle engine until "Check Engine" light comes "ON." Code 22 should be stored in memory for at least 10 seconds after ignition is turned "OFF." If not, the ECM is faulty.
An intermittent "Check Engine" light with no stored code may be caused by:
Arcing at ignition coil, plug wires or spark plugs.
EST wires should be routed away from spark plug wires, ignition system components and alternator.
Poor power supply circuit connections.
"Check Engine" light wire to ECM shorted to ground (circuit BLU/PNK 03).
Diagnostic test lead to ECM shorted to ground (circuit 451)
Poor ECM ground connections.
Electrical system interference caused by a defective relay, ECM driven solenoid or switch. These problems cause an electrical surge and normally occur when the faulty component is operated.
Improper installation of accessories such as lights, sound systems, alarms, etc.
Hope this helps!
#1957 of 2305 Re: ALDL location [atfdmike]
May 18, 2006 (9:16 am)
thank you. You information does concur with mine. I prevoiusly went from constant check engine to intermitent check engine by replace fuel and exhaust components and I do have a shortage/battery drain to locate. It takes about a week to kill a new battery even with positive cable disconnected. Heater switch wil run with ignition off so I suspect it....It is not the alternator nor is it a bad battery....I have not thouroughly checked the ignition system. I still have to find that plug though.....I just don't see the aldl harness? I will also remove those strange loose wires left by the previous owner.....I will post to group in new message for location of aldl harness.
Thank you Supertech,
#1958 of 2305 Where's the harness? 92 Rodeo ALDL Location diagnostics..92 rodeo v6 3.1L
May 18, 2006 (9:27 am)
The repair manual states and shows diagrams of the ALDL harness to check computer codes at home. I cannot see this harness. Has anyone seen the harness? The book says under driver side dash to the left. Here is a pic set by atfdmike of the diagram from the book. http://www.carspace.com/atfdmike/.59a46397!v=
This Rodeo has had almost everything replaced so feel free to post questions..
#1959 of 2305 Re: Where's the harness? 92 Rodeo ALDL Location diagnostics..92 rodeo v6 3.1L [hikick1]
May 18, 2006 (10:59 am)
I don't know if I missed something, or was just unclear in my previous post,but the repair manual I use states that the diagnostic link connector is in the center console for your year Rodeo. It does refer in other areas to the LH kick panel but, I know that older models of the trooper also have the aldl connector there in the center console. I would try looking there for the pictured connector. Have you looked there for the connector yet? If not, let us know if you find it there. Best!
#1960 of 2305 How to relieve overcharge A/C system
May 18, 2006 (6:25 pm)
Hi, I accidentalty overcharged my 2000 Rodeo A/C. I tried to relieve the R134a by pressing the low pressure valve. I see mostly oil come (shoot) out of the valve instead of the refrigerant so I stop. What is the proper way to release some of the refrigerant? I do have the little gage that come with the charging bottle. Thanks in advance.
#1961 of 2305 Re: How to relieve overcharge A/C system [khanh1]
May 19, 2006 (7:38 am)
Hi, You don't say why you added the refrigerant or how much, but usually it is recovered through a recycling unit and can be reused and not released to atmosphere.
I am not suggesting you release the refrigerant, but usually it takes some time of normal AC operation for the oil to settle down after running the AC, at which time it will usually end up in the compressor sump and the accumulator(receiver)/dryer bottle (if equipped). Once it settles, shutting down the system will leave most of the oil intact, and the slow release of pressure from an ambient system will not release a lot of oil at the same time. Unfortunately, you have no way of recovering what you release so that you can measure it. If you attempt it, there will be some oil moving when you start releasing, so short of using a recycling station, oil will be released along with the refrigerant.
With ALL this in mind, the best answer is to have the system totally evacuated and drained by a suitable mechanic, at which time you can then add the proper amounts and type of oil and refrigerant and be assured that no ill results will take place. Your system holds by total amount only 5 ounces of oil and 1.43 pounds of refrig according to the manual. the oil is special and is a Polyalkaline Glycol (PAG) refrigerant oil. PAG refrigerant oil has a slight blue tint. The oil is hydroscopic (absorbs water from the atmosphere).
One guys opinion, hope it helps. Maybe others have other ideas.
#1962 of 2305 Re: 99 Rodeo ABS [jmorr1]
May 19, 2006 (9:28 pm)
I have a 2000 Rodeo doing this same thing...did you find out the solution? My Rodeo dealer can't seem to find out the problem nor any other mechanic, and I have already bumped into another vehicle and shot into intersections. Thanks
#1963 of 2305 How to check diagnostic codes at home in 5 minutes? 92 Rodeo-ALDL
May 20, 2006 (10:03 am)
I finally found that harness. I will clarify the book description in case anyone else wishes to perform this proceedure. The harness is located as a direct connection from the ecu(brainbox)..(located on the wall just past the driver door. You may have to remove a small panel and pull back the carpet to see the connector and ecu. You will be looking at the front of the harness. Flip to back of the black harness to see a picture like in the diagram. My 92 is equipped with two different set of terminals for diagnosis. This was not mentioned in the repair book. One set is>>>: It has the 2.3L style "plug and play" connectors. Two wires are taped together. They are blue and white. Plug them together. Turn the ignition to where dash lights up but DO NOT TURN ON ENGINE. The dash lights will flash three times by three times (9 times)...before beginning diagnostic proceeedure. THE OTHER WAY>>>>The aldl black terminal as described in the manual..Put a paper clip into the two terminals A&B(upper right pins). One end of the paper clip in A and the other end into B. Turn on ignition but do not turn on motor. The dash will flash then give codes if there are any. Need codes? just e-mail.....need photos? Just email. This is simple and can save lots of time and money...
#1964 of 2305 Re: How to check diagnostic codes at home in 5 minutes? 92 Rodeo-ALDL [hikick1]
by Stever@Edmunds HOST
May 20, 2006 (11:15 am)
Check out - it's a good place to make albums and post your photos. All you need to do is login with your Edmunds user name and password.
That way someone stumbling onto your post in a year or two will easily find the photos.