Check
1. Remove the fuel tank (see Chapter 4). Check the coils visually for loose or damaged terminals, cracks and other damage.
2. Remove the seat (see Chapter 8). Disconnect the battery negative (-) lead.
3. Remove the coil being tested (see Steps 16 to 18).
Primary windings check - all models
4. Set an ohmmeter or multimeter to the ohms x 1 scale and measure the resistance between the primary circuit terminals on the coil (see illustration). This will give a resistance reading of the primary windings of the coil and should be consistent with the value given in the Specifications at the beginning of the Chapter.
3.4. To test the HT coil primary resistance, connect the multimeter leads between the primary circuit terminals
Secondary windings check - all models
5. To check the condition of the secondary windings, set the meter to the K-ohm scale.
6. On XL600V-H to R (1987 to 1995) models and XRV750-L Io S (1990 to 1995) models, connect one meter probe to the spark plug cap and the other probe to the green primary circuit terminal on the coil.
7. On XL600V-T to X (1997 to 1999) models. XL650V models and XRV750-T models onward (1996-on), connect one meter probe to one spark plug cap and the other probe to the other cap (see illustration).
3.7. To test the HT coil secondary resistance, connect the multimeter leads between the spark plug sockets
8. If, on all models, the reading obtained is not within the range shown in the Specifications, unscrew the cap(s) from the end of the HT lead(s) and repeat the measurement. If the reading is now as specified, then the cap(s) could be faulty. To test the cap(s). measure the resistance, which should be around 5 K-ohms (see illustration).
3.8. Measuring spark plug cap resistance
9. If the caps are good, separate the lead from the coil by unscrewing its retainer, and check the lead for continuity (zero resistance). If there is no continuity (i.e. a very high resistance), the lead is faulty. With the lead(s) detached, recheck the coil. If the coil reading is still outside the specified range, it is likely that the coil is defective.
10. It is advisable to confirm your findings with a Honda dealer before buying a new coil. Note that on later models the following peak voltage test can be made to confirm the coil's condition.
Peak voltage test - XL600V-T to X (1997 to 1999) models, XL650V models and XRV750 T models onwards (1996-on)
11. Honda specify their own Imrie diagnostic tester (model 625), or the peak voltage adapter (Pt. No.07HGJ-0020100) with an aftermarket digital multimeter having an impedance of 10 M-ohm/DCV minimum, for the peak voltage test. If this equipment Is available, install and reconnect the coils as described in Steps 19 to 21.
12. Connect the positive (+) lead of the voltmeter and peak voltage adapter arrangement to the blue/yellow (front cylinder coil) or yellow/blue (rear cylinder coil) wire terminal on the coil, with the wiring connector still securely connected, and connect the negative (-) lead to a suitable earth (ground) point.
13. Check that the kill switch Is in the RUN position and the transmission is in neutral, then turn the ignition switch ON. Note the initial voltage reading on the meter, then turn the engine over on the starter motor and note the ignition coil peak voltage reading on the meter. Once both readings have been noted, turn the ignition switch off and disconnect the meter.
14. If the initial voltage reading is not as expected or the peak voltage readings are lower than the specified minimum (see Specifications) then a fault is present somewhere else in the ignition system circuit (see Section 2); note that the peak voltage readings for each coil can be different but each one must exceed the specified minimum.
15. If the initial and peak voltage readings are as specified and the plug does not spark, then the ignition HT coil, HT lead or plug cap are faulty (the plug caps and leads are available separately). In order to determine conclusively that an ignition coil is defective, it should be tested by a Honda dealer. If the coil is confirmed to be faulty, it must be renewed; the coil is a sealed unit and cannot therefore be repaired.
Removal
16. Remove the fuel tank (see Chapter 4). Mark the locations of all wires and leads before disconnecting them. The coils can now be removed. Note the spacers fitted on the coil mounting.
17. Disconnect the primary circuit wiring connectors from the coils (see illustration). Pull the caps off the spark plugs (see illustration 2.2).
3.17. Disconnect the primary wiring connectors (arrowed)
18. Unscrew the bolts/nuts securing the coil or its mounting bracket (according to model), noting the spacers, and remove the coil, noting how it fits (see illustrations).
3.18a. Rear cylinder HT coil mounting bolts (A), front cylinder coil (B) - XL600V single coil per cylinder models
3.18b. Front cylinder HT coil (arrowed) - XL650V
3.18c. Rear cylinder HT coil (arrowed) - XL650V
3.18d. Front cylinder HT coil (arrowed) - XRV single coil per cylinder models
3.18e. Rear cylinder HT coil (arrowed) - XRV single coil per cylinder models
Installation
19. Installation is the reverse of removal.
20. On models with two coils per cylinder, note that each coil is marked according to the spark plug it feeds, e.g. a coil marked FR-R is for the front cylinder right-hand spark plug. On models with one coll per cylinder, note that each HT lead is marked according to the spark plug it feeds, e.g. a lead marked FR-R is for the front cylinder right-hand spark plug (see illustration).
3.20. Note the markings as described and make sure all leads are correctly connected
21. Make sure the wiring connectors and HT leads are securely connected - on single HT lead coils, the black/blue (front) and black/yellow (rear) primary circuit wire connectors are for the black terminals on the coils, the green wire connectors are for the green terminals. On twin HT lead coils, the black/white wire connectors are for the black terminals, and the blue/yellow (front) or yellow/blue (rear) wire connectors are for the green terminals.