Question about 1985 Jeep CJ7

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Ignition Problems on 86 Jeep CJ7 No Spark From Coil??

So I have replaced the control module, starter solenoid, and coil and still no spark from the coil to the negative terminal for testing. I was told it should spark 6 times for every revolution and it will only spark once if at all. I checked the voltage and it was good (around 6v) when key is on but when cranking it is only around 8.8V and should be near 12V. I believe the resistance wire could be the problem. It says it should be 1.35 ohms and I found it around 1.8 ohms so it seems like it must be partly broken somewhere. Can I just jump 12V from the battery to the coil to check this or can it damage something?

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  • djw40880 May 03, 2009

    I have 85 cj7 with no spark to plugs...replaced cap, wires, plugs, coil and igntion control module. starter works fine and motor turns over fine. Jeep was running before these changes. Wires are on the correct plugs. I have tested for fire coming out of distributor and do not have any.

  • Anonymous May 06, 2009

    I get 1 spark when the ignition is turned off. No spark while cranking. I went through the book and no problem found. coil , module, and voltage all ok

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Check to see if u have 12v at the pick up coil in the dist. if not thats ur prob. my 81 cj7 304 v8 did it

Posted on May 25, 2009

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You can put 12 volts from the battery to the positive side of the coil with no problem.

Posted on Jan 08, 2009

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O5 Colorado got the ecm code when I shut off the truck and now it won't turn over


What ECM code ? What is everything else that is working ? Headlamps , inside lighting , radio etc... When you turn the key on do the instrument cluster warning lights come on then off a few seconds later ? Anti-theft (security light ) On ? Flashing ? Do you know what all is involved ,or happens when you turn the key to start ?
Circuit Description (ECM/PCM Controlled)
Moving the ignition switch to the START position sends a 12-volt signal to the engine control module (ECM)/powertrain control module (PCM) Crank Request circuit. The ECM/PCM verifies that the transmission is in the PARK or NEUTRAL position. With the transmission in Park, voltage flows through the Park/Neutral position switch and feeds the starter relay coil. The PCM then grounds the control circuit of the starter relay. When the starter relay is energized it allows battery positive voltage to the starter solenoid S terminal. On some vehicles the starter will continue to crank the engine with the key released until it starts or the crank command has timed out to prevent excessive heat build up in the starter circuitry or the ECM/PCM receives an engine run flag.
Circuit Description (BCM Controlled)
Moving the ignition to the START position signals the body control module (BCM) that engine crank has been requested. The BCM verifies that theft is not active and sends a serial data message to the powertrain control module (PCM) requesting engine start. The BCM also energizes the RUN/CRANK RELAY. When the RUN/CRANK RELAY switch side closes, and the vehicle is in Park or Neutral or with the clutch is fully depressed, if equipped, supplies voltage to the starter relay coil. The PCM verifies the transmission is in Park or Neutral and the clutch is fully depressed, if equipped. The PCM will then ground the control circuit of the starter relay, closing the switch supplying voltage to the starter solenoid. On some vehicles the starter will continue to crank the engine with the key released until it starts of the crank command has timed out to prevent excessive heat build up in the starter circuitry or the PCM receives an engine run flag.


Verify that no starter relay, immobilizer, or automatic transmission DTCs are set that would cause the PCM to disable starting.
? If the specified DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle .
Ignition ON, observe the scan tool PCM Ignition 1 Signal parameter with a scan tool. The reading should be greater than 10.0 Volts.
? If less than the specified value, test the ETC, PCM 1, and PCM B fuses, the RUN/CRNK relay, and the PCM ignition voltage circuits for an open/high resistance. If the circuits test normal, replace the PCM.
Ignition OFF, remove the START relay.
Verify that a test lamp illuminates between the B+ circuit terminal 30 and ground.
? If the test lamp does not illuminate, test the START fuse and the B+ circuit for an open/high resistance.
Ignition ON, transmission in Park or clutch pedal pressed, verify that a test lamp illuminates between the PNP/clutch start switch signal circuit terminal 86 and ground.
? If the test lamp does not illuminate, test the IGN fuse, RUN/CRANK relay, PNP/clutch switch ignition voltage circuit, and the signal circuit for a short to ground or an open/high resistance. If the circuits test normal, test or replace the PNP switch or the clutch start switch.
Connect a test lamp between the park/neutral signal circuit terminal 86 and the relay coil control circuit terminal 85.
Ignition ON, transmission in Park, or clutch pedal pressed, turn the ignition switch between the START and RUN positions. The test lamp should turn ON and OFF when changing between the commanded states.
? If the test lamp is always ON, test the relay control circuit for a short to ground. If the circuit tests normal, replace the PCM.
? If the test lamp is always OFF, test the relay control circuit for a short to voltage or an open/high resistance. Test the PNP/clutch start switch signal circuit for an open/high resistance. If the circuits test normal, replace the PCM.
Install the START relay.
Connect a test lamp between the starter solenoid terminal and ground.

Mar 12, 2017 | Cars & Trucks

1 Answer

1984 jeep cj7 258 I changed ign control module but still no spark what's the next move?


Did you check primary voltage to ignition coil? Goes hot with the key on, should be a red wire. If no voltage have to check wiring circuit and ignition switch. Primary voltage is just 12 volts, use a test light.

Nov 20, 2015 | Jeep Cars & Trucks

1 Answer

89ford escort no spark. replaced coil replaced pickupcoil control module and still no spark


Begin with the basics;
Scan....
Add test equipment;
Test for signal coil + terminal.....
Test for pulsating signal to coil neg terminal.....

May 19, 2015 | Ford Cars & Trucks

1 Answer

Put in a new battery last November and now you go to start it it just clicks


Check the battery terminals,and battery posts, they may need to be cleaned. Your local parts store sells a battery post and terminal cleaner brush. When disconnecting the battery besure not to cause any sparks and if you smoke put it out before starting any battery maintence. Take the negative terminal off first, clean but dont put it back on yet. take the positive terminal of and clean both the terminal and the battery post.. Have someone with a volt meter check the voltage in the battery, if it measures 12volts, if available, then install the positive terminal first, then the negative post last taking care not to create any sparks. Once that is done try to start the car. If it starts, you have fixed it. If not, then you will have to move on to the starter solenoid.on the left inner fender, the other end of the positive batery terminal cable hooks to it. Again take the negative battery terminal off and replace the solenoid. Pay close attention where the wires came off of. Once you have replaces the solenoid, hook the negative terminal back on to the battery. This should take care of the problem, If not then you have to take the starter off and take it to you local parts store and have it tested they will tell you if it is bad. That is the last thing in the starting circuit that will cause the clicking noise. I hope this information help you to sovle you problem.

Apr 01, 2013 | 1992 Ford Ranger

1 Answer

No power at all


Inspect/Test/Replace Hope this helps.

An ignition switch supplies voltage to the ignition control module and/or the ignition coil. Often an ignition sytem thas two wires connected to the run terminal of the ignition switch. On is connected to the module. The other is connected to the primary resistor and coil. The start terminal of the switch is also wired to the module.
You can check for voltage using either a 12-volt test light or a digital multimeter (dmm).
To use a test light:
  • Turn the ignition key off and disconnect the wire connector at the module.
  • Disconnect the S terminal of the starter solenoid to prevent the engine from cranking when the ignition is in the run position.
  • Turn the key to the run position and probe the red wire connection to check for voltage.
  • Check for voltage at the battery terminal of the ignition coil using the test light.
  • Next, turn the key to the start position and check for voltage at the white wire connector at the module and the battery terminal of the ignition coil. If voltage is present, the switch and its circuit are okay.
To do the same test using a DMM:
  • Turn the ignition switch to the off position and back-probe, with the meter's positive lead, the power feed wire at the module.
  • Connect the meter's negative to a good ground at the distributor base.
  • Turn the ignition to the run or start position as needed, and measure the voltage.
  • The reading should be at least 90% of battery voltage.

Dec 21, 2012 | 1999 Buick Regal

1 Answer

Engine turns but does not start items replaced so


Check the starter solenoid, or igintion switch

Feb 18, 2011 | 1994 Lincoln Continental

1 Answer

My 92 dakota is not getting any spark


Engine Fails To Start

The "Checking For Spark'' test should be performed prior to this test.

This is a basic test of the ignition system that systematically examines the battery, the coil, the engine controller, and its wiring harness and connections; the most likely culprits in a no-start condition at this stage.
88472304.gif

Fabricate this special jumper with a 0.33 MF capacitor in-line to test the ignition coil
Click to Enlarge

  1. Unplug the ignition coil harness connector at the coil.
  2. Connect a set of small jumper wires (18 gauge or smaller) between the disconnected harness terminals and the ignition coil terminals.
88472314.gif

Terminal locations on the engine controller 14-way connector-1989 models
Click to Enlarge 88472305.gif

Engine controller 60-way connector-relevant terminals for testing are shown numbered
Click to Enlarge

  1. Attach one lead of a a voltmeter to the positive (12V) jumper wire. Attach the negative side of the voltmeter to a good ground. Measure the voltage at the battery and confirm that enough current is available to operate the starting and ignition systems.
  2. Crank the engine for five seconds while monitoring the voltage at the coil positive terminal:
    1. If the voltage remains at zero, diagnosis of the fuel system should be performed. Also check the engine controller and auto shutdown relay.
    2. If voltage is at or near battery voltage and then drops to zero after one or two seconds of engine cranking, check the engine control module circuit.

WARNING

The ignition must be turned OFF prior to unplugging the engine controller connector. If it is not, electrical surging could occur causing damage to the unit or other electrical components in the vehicle.

  1. If the voltage remains at or near battery voltage during the entire five seconds, turn the ignition key OFF. Remove the 14-way connector on 1989 models, or the 60-way connector on 1990-96 models at the engine controller. Check the 14-way or 60-way connector for any spread terminals.
  1. Remove the test lead from the coil positive terminal. Connect an 18 gauge jumper wire between the battery positive terminal and the coil positive terminal.
  2. Make a special jumper cable (see illustration). Using the jumper MOMENTARILY ground terminal 12 on the 14-way connector (1989), or terminal 19 (see illustration) of the 1990-96 60-way connector. A spark should be generated at the coil wire when the ground is removed.
    1. If a spark is generated, replace the engine controller computer.
    2. If no spark is seen, use the special jumper to ground the coil negative terminal directly. If spark is produced, repair the wiring harness for an open circuit condition. If spark is not produced, replace the ignition coil
    this is for distributor ignition
THIS IS TESTING OF DISTRIBUTORLESS IGN
Testing

This procedure requires an ohmmeter to test the coil packs for primary and secondary resistance (specifications are given for an ambient temperature of 70-80°F/21-27°C).
88472320.gif

The two coil packs contain five independent coils, which fire paired cylinders (shown numbered)
Click to Enlarge

  1. Disconnect the negative battery cable.
  2. Determine the manufacturer of the coil. It should be labeled either a Diamond or Toyodenso.
88472779.gif

Location of critical terminals for checking the coil primary resistance-V10 engine front coils
Click to Enlarge 88472780.gif

Location of critical terminals for checking the coil primary resistance-V10 engine rear coils
Click to Enlarge

  1. Check the secondary resistance of each individual paired coil by connecting an ohmmeter across the coil towers. This must be done between the correct cylinder pairs: 3/2, 7/4, 1/6, 9/8, or 5/10. Resistance for a Diamond coil should be 11,300-15,300 ohms. For a Toyodenso manufactured coil pack, resistance should be 11,300-13,300 ohms.
88472323.gif

Use an ohmmeter to check secondary resistance as shown

  1. Check the primary resistance of the front coil pack by attaching an ohmmeter between the B+ coil terminal and either the right (cylinders 3/2), center (cylinder 7/4), or left coil (cylinders 1/6) terminals. Resistance for a Diamond coil should be 0.97-1.18 ohms. Resistance for a Toyodenso coil should be 0.95-1.20 ohms.
  2. To test the primary resistance of the rear coil pack, attach an ohmmeter between the B+ coil terminal (see illustration) and either the right (cylinders 9/8), or left (cylinders 5/10) coil terminals. Resistance for a Diamond coil should be 0.97-1.18 ohms. Resistance for a Toyodenso coil should be 0.95-1.20 ohms.
i hope this helps any more questions repl if help at all plz vote or comment me

Jan 17, 2011 | 1995 Dodge Dakota

1 Answer

My 83 bronco won't start. I just replaced the ingnition module..had my coil tested which was good. Any thoughts?


Cap, rotor, wires, plugs... for starters (no pun) I assume you're not getting spark. Other possibilities ignition switch or small leads on solenoid. Did you disconnect your battery when installing module. There's a possibility if you did not that it shorted (power surge) when you plugged it in. They were very sensitive back then. The correct way WHENEVER you disconnect battery is positive first, negative ALWAYS last.

Jan 06, 2011 | Ford Bronco Cars & Trucks

1 Answer

I need to find out how to take off and put on a starter on a 2004 chevy tracker


TESTING WARNING
During the following test, the starter motor must not be energized for longer than 5 seconds, otherwise you run the risk of burning out the starter motor coil.
  1. Remove the starter motor from the vehicle.
  2. Detach the field coil lead from terminal M on the starter motor.
  3. Using jumper wires, connect a 12 volt battery to the starter motor so that the negative battery terminal is attached to the starter motor housing and to solenoid terminal M, and that the positive battery terminal is connected to starter motor solenoid terminal S. The starter motor plunger should move outward; if it does not, replace the solenoid with a new one. Fig. 1: To test the solenoid plunger, first detach the field coil lead from alternator terminal M, then attach a 12 volt battery to the starter motor as shown . . . 90882g50.gif
    Fig. 2: . . . then detach the negative jumper wire from terminal M. The plunger should remain extended 90882g51.gif
    Fig. 3: Detach the other negative lead from the starter motor housing. The solenoid plunger should now retract to its normal resting position 90882g52.gif
    Fig. 4: Use an ammeter to measure the amount of current draw the starter motor uses 90882g53.gif

  4. Detach the negative battery jumper wire from terminal M on the starter motor solenoid, and check the plunger for movement. The plunger should remain extended; if the plunger returns to its resting position, replace the solenoid with a new one.
  5. While observing the solenoid plunger, detach the negative battery lead from the starter motor housing. The plunger should return to its normal resting position; if it does not, replace the solenoid with a new one.
  6. Reattach the 12 volt battery and install an ammeter to the starter motor as shown in the accompanying illustration. The starter motor should rotate smoothly and steadily with the pinion gear moving out, and the ammeter should display less than 60 amps at 11.5 volts (Samurai models), or 90 amps at 11 volts (Sidekick, Tracker, X-90 and Sidekick Sport models). If the ammeter does not display the specified values, or if the starter motor does not operate smoothly and steadily, replace the starter motor with a new one.
---
REMOVAL & INSTALLATION
  1. Disconnect the negative battery cable.
  2. If necessary for added under-vehicle clearance, apply the parking brake, block the rear wheels, then raise and safely support the front of the vehicle on jackstands.
  3. From beneath the vehicle, label and detach all wiring from the starter motor solenoid terminals.
  4. Remove one of the two starter motor mounting bolts and loosen the other bolt until it can be turned by hand, then support the starter motor with one hand while removing the last starter motor mounting bolt.
  5. Lower the starter motor down and away from the engine and transmission. To install:
  6. Hold the starter motor in position and install the two mounting bolts. Tighten the two bolts securely.
  7. Reattach all applicable wiring to the starter motor solenoid. Ensure that the wiring terminals and connectors are clean and free of corrosion.
  8. If necessary, lower the vehicle.
  9. Connect the negative battery cable.

Oct 23, 2010 | Chevrolet Tracker Cars & Trucks

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